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29275b1d17
Reported-by: Michael Paquier Discussion: https://postgr.es/m/ZZKTDPxBBMt3C0J9@paquier.xyz Backpatch-through: 12
4490 lines
141 KiB
C
4490 lines
141 KiB
C
/*-------------------------------------------------------------------------
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*
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* nodeModifyTable.c
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* routines to handle ModifyTable nodes.
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*
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* Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* src/backend/executor/nodeModifyTable.c
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*
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*-------------------------------------------------------------------------
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*/
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/* INTERFACE ROUTINES
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* ExecInitModifyTable - initialize the ModifyTable node
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* ExecModifyTable - retrieve the next tuple from the node
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* ExecEndModifyTable - shut down the ModifyTable node
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* ExecReScanModifyTable - rescan the ModifyTable node
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*
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* NOTES
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* The ModifyTable node receives input from its outerPlan, which is
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* the data to insert for INSERT cases, the changed columns' new
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* values plus row-locating info for UPDATE and MERGE cases, or just the
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* row-locating info for DELETE cases.
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*
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* MERGE runs a join between the source relation and the target
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* table; if any WHEN NOT MATCHED clauses are present, then the
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* join is an outer join. In this case, any unmatched tuples will
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* have NULL row-locating info, and only INSERT can be run. But for
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* matched tuples, then row-locating info is used to determine the
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* tuple to UPDATE or DELETE. When all clauses are WHEN MATCHED,
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* then an inner join is used, so all tuples contain row-locating info.
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*
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* If the query specifies RETURNING, then the ModifyTable returns a
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* RETURNING tuple after completing each row insert, update, or delete.
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* It must be called again to continue the operation. Without RETURNING,
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* we just loop within the node until all the work is done, then
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* return NULL. This avoids useless call/return overhead. (MERGE does
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* not support RETURNING.)
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*/
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#include "postgres.h"
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#include "access/heapam.h"
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#include "access/htup_details.h"
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#include "access/tableam.h"
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#include "access/xact.h"
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#include "catalog/catalog.h"
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#include "commands/trigger.h"
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#include "executor/execPartition.h"
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#include "executor/executor.h"
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#include "executor/nodeModifyTable.h"
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#include "foreign/fdwapi.h"
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#include "miscadmin.h"
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#include "nodes/nodeFuncs.h"
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#include "optimizer/optimizer.h"
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#include "rewrite/rewriteHandler.h"
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#include "storage/bufmgr.h"
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#include "storage/lmgr.h"
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#include "utils/builtins.h"
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#include "utils/datum.h"
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#include "utils/memutils.h"
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#include "utils/rel.h"
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typedef struct MTTargetRelLookup
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{
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Oid relationOid; /* hash key, must be first */
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int relationIndex; /* rel's index in resultRelInfo[] array */
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} MTTargetRelLookup;
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/*
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* Context struct for a ModifyTable operation, containing basic execution
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* state and some output variables populated by ExecUpdateAct() and
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* ExecDeleteAct() to report the result of their actions to callers.
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*/
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typedef struct ModifyTableContext
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{
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/* Operation state */
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ModifyTableState *mtstate;
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EPQState *epqstate;
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EState *estate;
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/*
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* Slot containing tuple obtained from ModifyTable's subplan. Used to
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* access "junk" columns that are not going to be stored.
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*/
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TupleTableSlot *planSlot;
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/* MERGE specific */
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MergeActionState *relaction; /* MERGE action in progress */
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/*
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* Information about the changes that were made concurrently to a tuple
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* being updated or deleted
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*/
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TM_FailureData tmfd;
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/*
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* The tuple projected by the INSERT's RETURNING clause, when doing a
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* cross-partition UPDATE
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*/
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TupleTableSlot *cpUpdateReturningSlot;
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} ModifyTableContext;
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/*
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* Context struct containing output data specific to UPDATE operations.
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*/
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typedef struct UpdateContext
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{
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bool updated; /* did UPDATE actually occur? */
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bool crossPartUpdate; /* was it a cross-partition update? */
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TU_UpdateIndexes updateIndexes; /* Which index updates are required? */
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/*
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* Lock mode to acquire on the latest tuple version before performing
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* EvalPlanQual on it
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*/
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LockTupleMode lockmode;
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} UpdateContext;
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static void ExecBatchInsert(ModifyTableState *mtstate,
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ResultRelInfo *resultRelInfo,
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TupleTableSlot **slots,
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TupleTableSlot **planSlots,
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int numSlots,
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EState *estate,
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bool canSetTag);
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static void ExecPendingInserts(EState *estate);
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static void ExecCrossPartitionUpdateForeignKey(ModifyTableContext *context,
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ResultRelInfo *sourcePartInfo,
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ResultRelInfo *destPartInfo,
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ItemPointer tupleid,
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TupleTableSlot *oldslot,
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TupleTableSlot *newslot);
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static bool ExecOnConflictUpdate(ModifyTableContext *context,
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ResultRelInfo *resultRelInfo,
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ItemPointer conflictTid,
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TupleTableSlot *excludedSlot,
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bool canSetTag,
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TupleTableSlot **returning);
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static TupleTableSlot *ExecPrepareTupleRouting(ModifyTableState *mtstate,
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EState *estate,
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PartitionTupleRouting *proute,
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ResultRelInfo *targetRelInfo,
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TupleTableSlot *slot,
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ResultRelInfo **partRelInfo);
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static TupleTableSlot *ExecMerge(ModifyTableContext *context,
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ResultRelInfo *resultRelInfo,
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ItemPointer tupleid,
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bool canSetTag);
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static void ExecInitMerge(ModifyTableState *mtstate, EState *estate);
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static bool ExecMergeMatched(ModifyTableContext *context,
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ResultRelInfo *resultRelInfo,
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ItemPointer tupleid,
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bool canSetTag);
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static void ExecMergeNotMatched(ModifyTableContext *context,
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ResultRelInfo *resultRelInfo,
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bool canSetTag);
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/*
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* Verify that the tuples to be produced by INSERT match the
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* target relation's rowtype
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*
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* We do this to guard against stale plans. If plan invalidation is
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* functioning properly then we should never get a failure here, but better
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* safe than sorry. Note that this is called after we have obtained lock
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* on the target rel, so the rowtype can't change underneath us.
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*
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* The plan output is represented by its targetlist, because that makes
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* handling the dropped-column case easier.
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*
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* We used to use this for UPDATE as well, but now the equivalent checks
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* are done in ExecBuildUpdateProjection.
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*/
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static void
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ExecCheckPlanOutput(Relation resultRel, List *targetList)
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{
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TupleDesc resultDesc = RelationGetDescr(resultRel);
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int attno = 0;
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ListCell *lc;
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foreach(lc, targetList)
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{
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TargetEntry *tle = (TargetEntry *) lfirst(lc);
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Form_pg_attribute attr;
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Assert(!tle->resjunk); /* caller removed junk items already */
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if (attno >= resultDesc->natts)
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ereport(ERROR,
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(errcode(ERRCODE_DATATYPE_MISMATCH),
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errmsg("table row type and query-specified row type do not match"),
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errdetail("Query has too many columns.")));
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attr = TupleDescAttr(resultDesc, attno);
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attno++;
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if (!attr->attisdropped)
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{
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/* Normal case: demand type match */
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if (exprType((Node *) tle->expr) != attr->atttypid)
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ereport(ERROR,
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(errcode(ERRCODE_DATATYPE_MISMATCH),
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errmsg("table row type and query-specified row type do not match"),
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errdetail("Table has type %s at ordinal position %d, but query expects %s.",
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format_type_be(attr->atttypid),
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attno,
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format_type_be(exprType((Node *) tle->expr)))));
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}
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else
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{
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/*
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* For a dropped column, we can't check atttypid (it's likely 0).
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* In any case the planner has most likely inserted an INT4 null.
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* What we insist on is just *some* NULL constant.
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*/
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if (!IsA(tle->expr, Const) ||
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!((Const *) tle->expr)->constisnull)
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ereport(ERROR,
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(errcode(ERRCODE_DATATYPE_MISMATCH),
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errmsg("table row type and query-specified row type do not match"),
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errdetail("Query provides a value for a dropped column at ordinal position %d.",
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attno)));
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}
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}
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if (attno != resultDesc->natts)
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ereport(ERROR,
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(errcode(ERRCODE_DATATYPE_MISMATCH),
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errmsg("table row type and query-specified row type do not match"),
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errdetail("Query has too few columns.")));
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}
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/*
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* ExecProcessReturning --- evaluate a RETURNING list
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*
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* resultRelInfo: current result rel
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* tupleSlot: slot holding tuple actually inserted/updated/deleted
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* planSlot: slot holding tuple returned by top subplan node
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*
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* Note: If tupleSlot is NULL, the FDW should have already provided econtext's
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* scan tuple.
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*
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* Returns a slot holding the result tuple
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*/
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static TupleTableSlot *
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ExecProcessReturning(ResultRelInfo *resultRelInfo,
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TupleTableSlot *tupleSlot,
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TupleTableSlot *planSlot)
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{
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ProjectionInfo *projectReturning = resultRelInfo->ri_projectReturning;
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ExprContext *econtext = projectReturning->pi_exprContext;
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/* Make tuple and any needed join variables available to ExecProject */
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if (tupleSlot)
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econtext->ecxt_scantuple = tupleSlot;
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econtext->ecxt_outertuple = planSlot;
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/*
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* RETURNING expressions might reference the tableoid column, so
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* reinitialize tts_tableOid before evaluating them.
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*/
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econtext->ecxt_scantuple->tts_tableOid =
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RelationGetRelid(resultRelInfo->ri_RelationDesc);
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/* Compute the RETURNING expressions */
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return ExecProject(projectReturning);
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}
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/*
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* ExecCheckTupleVisible -- verify tuple is visible
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*
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* It would not be consistent with guarantees of the higher isolation levels to
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* proceed with avoiding insertion (taking speculative insertion's alternative
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* path) on the basis of another tuple that is not visible to MVCC snapshot.
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* Check for the need to raise a serialization failure, and do so as necessary.
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*/
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static void
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ExecCheckTupleVisible(EState *estate,
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Relation rel,
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TupleTableSlot *slot)
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{
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if (!IsolationUsesXactSnapshot())
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return;
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if (!table_tuple_satisfies_snapshot(rel, slot, estate->es_snapshot))
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{
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Datum xminDatum;
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TransactionId xmin;
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bool isnull;
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xminDatum = slot_getsysattr(slot, MinTransactionIdAttributeNumber, &isnull);
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Assert(!isnull);
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xmin = DatumGetTransactionId(xminDatum);
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/*
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* We should not raise a serialization failure if the conflict is
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* against a tuple inserted by our own transaction, even if it's not
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* visible to our snapshot. (This would happen, for example, if
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* conflicting keys are proposed for insertion in a single command.)
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*/
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if (!TransactionIdIsCurrentTransactionId(xmin))
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ereport(ERROR,
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(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
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errmsg("could not serialize access due to concurrent update")));
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}
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}
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/*
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* ExecCheckTIDVisible -- convenience variant of ExecCheckTupleVisible()
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*/
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static void
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ExecCheckTIDVisible(EState *estate,
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ResultRelInfo *relinfo,
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ItemPointer tid,
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TupleTableSlot *tempSlot)
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{
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Relation rel = relinfo->ri_RelationDesc;
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/* Redundantly check isolation level */
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if (!IsolationUsesXactSnapshot())
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return;
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if (!table_tuple_fetch_row_version(rel, tid, SnapshotAny, tempSlot))
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elog(ERROR, "failed to fetch conflicting tuple for ON CONFLICT");
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ExecCheckTupleVisible(estate, rel, tempSlot);
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ExecClearTuple(tempSlot);
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}
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/*
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* Initialize to compute stored generated columns for a tuple
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*
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* This fills the resultRelInfo's ri_GeneratedExprsI/ri_NumGeneratedNeededI
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* or ri_GeneratedExprsU/ri_NumGeneratedNeededU fields, depending on cmdtype.
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* If cmdType == CMD_UPDATE, the ri_extraUpdatedCols field is filled too.
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*
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* Note: usually, a given query would need only one of ri_GeneratedExprsI and
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* ri_GeneratedExprsU per result rel; but MERGE can need both, and so can
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* cross-partition UPDATEs, since a partition might be the target of both
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* UPDATE and INSERT actions.
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*/
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void
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ExecInitStoredGenerated(ResultRelInfo *resultRelInfo,
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EState *estate,
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CmdType cmdtype)
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{
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Relation rel = resultRelInfo->ri_RelationDesc;
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TupleDesc tupdesc = RelationGetDescr(rel);
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int natts = tupdesc->natts;
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ExprState **ri_GeneratedExprs;
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int ri_NumGeneratedNeeded;
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Bitmapset *updatedCols;
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MemoryContext oldContext;
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/* Nothing to do if no generated columns */
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if (!(tupdesc->constr && tupdesc->constr->has_generated_stored))
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return;
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/*
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* In an UPDATE, we can skip computing any generated columns that do not
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* depend on any UPDATE target column. But if there is a BEFORE ROW
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* UPDATE trigger, we cannot skip because the trigger might change more
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* columns.
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*/
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if (cmdtype == CMD_UPDATE &&
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!(rel->trigdesc && rel->trigdesc->trig_update_before_row))
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updatedCols = ExecGetUpdatedCols(resultRelInfo, estate);
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else
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updatedCols = NULL;
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/*
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* Make sure these data structures are built in the per-query memory
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* context so they'll survive throughout the query.
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*/
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oldContext = MemoryContextSwitchTo(estate->es_query_cxt);
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ri_GeneratedExprs = (ExprState **) palloc0(natts * sizeof(ExprState *));
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ri_NumGeneratedNeeded = 0;
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for (int i = 0; i < natts; i++)
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{
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if (TupleDescAttr(tupdesc, i)->attgenerated == ATTRIBUTE_GENERATED_STORED)
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{
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Expr *expr;
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/* Fetch the GENERATED AS expression tree */
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expr = (Expr *) build_column_default(rel, i + 1);
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if (expr == NULL)
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elog(ERROR, "no generation expression found for column number %d of table \"%s\"",
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i + 1, RelationGetRelationName(rel));
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/*
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* If it's an update with a known set of update target columns,
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* see if we can skip the computation.
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*/
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if (updatedCols)
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{
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Bitmapset *attrs_used = NULL;
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pull_varattnos((Node *) expr, 1, &attrs_used);
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if (!bms_overlap(updatedCols, attrs_used))
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continue; /* need not update this column */
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}
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/* No luck, so prepare the expression for execution */
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ri_GeneratedExprs[i] = ExecPrepareExpr(expr, estate);
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ri_NumGeneratedNeeded++;
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/* If UPDATE, mark column in resultRelInfo->ri_extraUpdatedCols */
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if (cmdtype == CMD_UPDATE)
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resultRelInfo->ri_extraUpdatedCols =
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bms_add_member(resultRelInfo->ri_extraUpdatedCols,
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i + 1 - FirstLowInvalidHeapAttributeNumber);
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}
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}
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/* Save in appropriate set of fields */
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if (cmdtype == CMD_UPDATE)
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{
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/* Don't call twice */
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Assert(resultRelInfo->ri_GeneratedExprsU == NULL);
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resultRelInfo->ri_GeneratedExprsU = ri_GeneratedExprs;
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resultRelInfo->ri_NumGeneratedNeededU = ri_NumGeneratedNeeded;
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}
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else
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{
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/* Don't call twice */
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Assert(resultRelInfo->ri_GeneratedExprsI == NULL);
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resultRelInfo->ri_GeneratedExprsI = ri_GeneratedExprs;
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resultRelInfo->ri_NumGeneratedNeededI = ri_NumGeneratedNeeded;
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}
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MemoryContextSwitchTo(oldContext);
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}
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/*
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* Compute stored generated columns for a tuple
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*/
|
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void
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ExecComputeStoredGenerated(ResultRelInfo *resultRelInfo,
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EState *estate, TupleTableSlot *slot,
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CmdType cmdtype)
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{
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Relation rel = resultRelInfo->ri_RelationDesc;
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TupleDesc tupdesc = RelationGetDescr(rel);
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int natts = tupdesc->natts;
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ExprContext *econtext = GetPerTupleExprContext(estate);
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ExprState **ri_GeneratedExprs;
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MemoryContext oldContext;
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Datum *values;
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bool *nulls;
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/* We should not be called unless this is true */
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Assert(tupdesc->constr && tupdesc->constr->has_generated_stored);
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/*
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* Initialize the expressions if we didn't already, and check whether we
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* can exit early because nothing needs to be computed.
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*/
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if (cmdtype == CMD_UPDATE)
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{
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if (resultRelInfo->ri_GeneratedExprsU == NULL)
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ExecInitStoredGenerated(resultRelInfo, estate, cmdtype);
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if (resultRelInfo->ri_NumGeneratedNeededU == 0)
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return;
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ri_GeneratedExprs = resultRelInfo->ri_GeneratedExprsU;
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}
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else
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{
|
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if (resultRelInfo->ri_GeneratedExprsI == NULL)
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ExecInitStoredGenerated(resultRelInfo, estate, cmdtype);
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/* Early exit is impossible given the prior Assert */
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Assert(resultRelInfo->ri_NumGeneratedNeededI > 0);
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ri_GeneratedExprs = resultRelInfo->ri_GeneratedExprsI;
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}
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oldContext = MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
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values = palloc(sizeof(*values) * natts);
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nulls = palloc(sizeof(*nulls) * natts);
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slot_getallattrs(slot);
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memcpy(nulls, slot->tts_isnull, sizeof(*nulls) * natts);
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for (int i = 0; i < natts; i++)
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{
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Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
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if (ri_GeneratedExprs[i])
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{
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Datum val;
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bool isnull;
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Assert(attr->attgenerated == ATTRIBUTE_GENERATED_STORED);
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econtext->ecxt_scantuple = slot;
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val = ExecEvalExpr(ri_GeneratedExprs[i], econtext, &isnull);
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/*
|
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* We must make a copy of val as we have no guarantees about where
|
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* memory for a pass-by-reference Datum is located.
|
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*/
|
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if (!isnull)
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val = datumCopy(val, attr->attbyval, attr->attlen);
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|
|
values[i] = val;
|
|
nulls[i] = isnull;
|
|
}
|
|
else
|
|
{
|
|
if (!nulls[i])
|
|
values[i] = datumCopy(slot->tts_values[i], attr->attbyval, attr->attlen);
|
|
}
|
|
}
|
|
|
|
ExecClearTuple(slot);
|
|
memcpy(slot->tts_values, values, sizeof(*values) * natts);
|
|
memcpy(slot->tts_isnull, nulls, sizeof(*nulls) * natts);
|
|
ExecStoreVirtualTuple(slot);
|
|
ExecMaterializeSlot(slot);
|
|
|
|
MemoryContextSwitchTo(oldContext);
|
|
}
|
|
|
|
/*
|
|
* ExecInitInsertProjection
|
|
* Do one-time initialization of projection data for INSERT tuples.
|
|
*
|
|
* INSERT queries may need a projection to filter out junk attrs in the tlist.
|
|
*
|
|
* This is also a convenient place to verify that the
|
|
* output of an INSERT matches the target table.
|
|
*/
|
|
static void
|
|
ExecInitInsertProjection(ModifyTableState *mtstate,
|
|
ResultRelInfo *resultRelInfo)
|
|
{
|
|
ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
|
|
Plan *subplan = outerPlan(node);
|
|
EState *estate = mtstate->ps.state;
|
|
List *insertTargetList = NIL;
|
|
bool need_projection = false;
|
|
ListCell *l;
|
|
|
|
/* Extract non-junk columns of the subplan's result tlist. */
|
|
foreach(l, subplan->targetlist)
|
|
{
|
|
TargetEntry *tle = (TargetEntry *) lfirst(l);
|
|
|
|
if (!tle->resjunk)
|
|
insertTargetList = lappend(insertTargetList, tle);
|
|
else
|
|
need_projection = true;
|
|
}
|
|
|
|
/*
|
|
* The junk-free list must produce a tuple suitable for the result
|
|
* relation.
|
|
*/
|
|
ExecCheckPlanOutput(resultRelInfo->ri_RelationDesc, insertTargetList);
|
|
|
|
/* We'll need a slot matching the table's format. */
|
|
resultRelInfo->ri_newTupleSlot =
|
|
table_slot_create(resultRelInfo->ri_RelationDesc,
|
|
&estate->es_tupleTable);
|
|
|
|
/* Build ProjectionInfo if needed (it probably isn't). */
|
|
if (need_projection)
|
|
{
|
|
TupleDesc relDesc = RelationGetDescr(resultRelInfo->ri_RelationDesc);
|
|
|
|
/* need an expression context to do the projection */
|
|
if (mtstate->ps.ps_ExprContext == NULL)
|
|
ExecAssignExprContext(estate, &mtstate->ps);
|
|
|
|
resultRelInfo->ri_projectNew =
|
|
ExecBuildProjectionInfo(insertTargetList,
|
|
mtstate->ps.ps_ExprContext,
|
|
resultRelInfo->ri_newTupleSlot,
|
|
&mtstate->ps,
|
|
relDesc);
|
|
}
|
|
|
|
resultRelInfo->ri_projectNewInfoValid = true;
|
|
}
|
|
|
|
/*
|
|
* ExecInitUpdateProjection
|
|
* Do one-time initialization of projection data for UPDATE tuples.
|
|
*
|
|
* UPDATE always needs a projection, because (1) there's always some junk
|
|
* attrs, and (2) we may need to merge values of not-updated columns from
|
|
* the old tuple into the final tuple. In UPDATE, the tuple arriving from
|
|
* the subplan contains only new values for the changed columns, plus row
|
|
* identity info in the junk attrs.
|
|
*
|
|
* This is "one-time" for any given result rel, but we might touch more than
|
|
* one result rel in the course of an inherited UPDATE, and each one needs
|
|
* its own projection due to possible column order variation.
|
|
*
|
|
* This is also a convenient place to verify that the output of an UPDATE
|
|
* matches the target table (ExecBuildUpdateProjection does that).
|
|
*/
|
|
static void
|
|
ExecInitUpdateProjection(ModifyTableState *mtstate,
|
|
ResultRelInfo *resultRelInfo)
|
|
{
|
|
ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
|
|
Plan *subplan = outerPlan(node);
|
|
EState *estate = mtstate->ps.state;
|
|
TupleDesc relDesc = RelationGetDescr(resultRelInfo->ri_RelationDesc);
|
|
int whichrel;
|
|
List *updateColnos;
|
|
|
|
/*
|
|
* Usually, mt_lastResultIndex matches the target rel. If it happens not
|
|
* to, we can get the index the hard way with an integer division.
|
|
*/
|
|
whichrel = mtstate->mt_lastResultIndex;
|
|
if (resultRelInfo != mtstate->resultRelInfo + whichrel)
|
|
{
|
|
whichrel = resultRelInfo - mtstate->resultRelInfo;
|
|
Assert(whichrel >= 0 && whichrel < mtstate->mt_nrels);
|
|
}
|
|
|
|
updateColnos = (List *) list_nth(node->updateColnosLists, whichrel);
|
|
|
|
/*
|
|
* For UPDATE, we use the old tuple to fill up missing values in the tuple
|
|
* produced by the subplan to get the new tuple. We need two slots, both
|
|
* matching the table's desired format.
|
|
*/
|
|
resultRelInfo->ri_oldTupleSlot =
|
|
table_slot_create(resultRelInfo->ri_RelationDesc,
|
|
&estate->es_tupleTable);
|
|
resultRelInfo->ri_newTupleSlot =
|
|
table_slot_create(resultRelInfo->ri_RelationDesc,
|
|
&estate->es_tupleTable);
|
|
|
|
/* need an expression context to do the projection */
|
|
if (mtstate->ps.ps_ExprContext == NULL)
|
|
ExecAssignExprContext(estate, &mtstate->ps);
|
|
|
|
resultRelInfo->ri_projectNew =
|
|
ExecBuildUpdateProjection(subplan->targetlist,
|
|
false, /* subplan did the evaluation */
|
|
updateColnos,
|
|
relDesc,
|
|
mtstate->ps.ps_ExprContext,
|
|
resultRelInfo->ri_newTupleSlot,
|
|
&mtstate->ps);
|
|
|
|
resultRelInfo->ri_projectNewInfoValid = true;
|
|
}
|
|
|
|
/*
|
|
* ExecGetInsertNewTuple
|
|
* This prepares a "new" tuple ready to be inserted into given result
|
|
* relation, by removing any junk columns of the plan's output tuple
|
|
* and (if necessary) coercing the tuple to the right tuple format.
|
|
*/
|
|
static TupleTableSlot *
|
|
ExecGetInsertNewTuple(ResultRelInfo *relinfo,
|
|
TupleTableSlot *planSlot)
|
|
{
|
|
ProjectionInfo *newProj = relinfo->ri_projectNew;
|
|
ExprContext *econtext;
|
|
|
|
/*
|
|
* If there's no projection to be done, just make sure the slot is of the
|
|
* right type for the target rel. If the planSlot is the right type we
|
|
* can use it as-is, else copy the data into ri_newTupleSlot.
|
|
*/
|
|
if (newProj == NULL)
|
|
{
|
|
if (relinfo->ri_newTupleSlot->tts_ops != planSlot->tts_ops)
|
|
{
|
|
ExecCopySlot(relinfo->ri_newTupleSlot, planSlot);
|
|
return relinfo->ri_newTupleSlot;
|
|
}
|
|
else
|
|
return planSlot;
|
|
}
|
|
|
|
/*
|
|
* Else project; since the projection output slot is ri_newTupleSlot, this
|
|
* will also fix any slot-type problem.
|
|
*
|
|
* Note: currently, this is dead code, because INSERT cases don't receive
|
|
* any junk columns so there's never a projection to be done.
|
|
*/
|
|
econtext = newProj->pi_exprContext;
|
|
econtext->ecxt_outertuple = planSlot;
|
|
return ExecProject(newProj);
|
|
}
|
|
|
|
/*
|
|
* ExecGetUpdateNewTuple
|
|
* This prepares a "new" tuple by combining an UPDATE subplan's output
|
|
* tuple (which contains values of changed columns) with unchanged
|
|
* columns taken from the old tuple.
|
|
*
|
|
* The subplan tuple might also contain junk columns, which are ignored.
|
|
* Note that the projection also ensures we have a slot of the right type.
|
|
*/
|
|
TupleTableSlot *
|
|
ExecGetUpdateNewTuple(ResultRelInfo *relinfo,
|
|
TupleTableSlot *planSlot,
|
|
TupleTableSlot *oldSlot)
|
|
{
|
|
ProjectionInfo *newProj = relinfo->ri_projectNew;
|
|
ExprContext *econtext;
|
|
|
|
/* Use a few extra Asserts to protect against outside callers */
|
|
Assert(relinfo->ri_projectNewInfoValid);
|
|
Assert(planSlot != NULL && !TTS_EMPTY(planSlot));
|
|
Assert(oldSlot != NULL && !TTS_EMPTY(oldSlot));
|
|
|
|
econtext = newProj->pi_exprContext;
|
|
econtext->ecxt_outertuple = planSlot;
|
|
econtext->ecxt_scantuple = oldSlot;
|
|
return ExecProject(newProj);
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecInsert
|
|
*
|
|
* For INSERT, we have to insert the tuple into the target relation
|
|
* (or partition thereof) and insert appropriate tuples into the index
|
|
* relations.
|
|
*
|
|
* slot contains the new tuple value to be stored.
|
|
*
|
|
* Returns RETURNING result if any, otherwise NULL.
|
|
* *inserted_tuple is the tuple that's effectively inserted;
|
|
* *insert_destrel is the relation where it was inserted.
|
|
* These are only set on success.
|
|
*
|
|
* This may change the currently active tuple conversion map in
|
|
* mtstate->mt_transition_capture, so the callers must take care to
|
|
* save the previous value to avoid losing track of it.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static TupleTableSlot *
|
|
ExecInsert(ModifyTableContext *context,
|
|
ResultRelInfo *resultRelInfo,
|
|
TupleTableSlot *slot,
|
|
bool canSetTag,
|
|
TupleTableSlot **inserted_tuple,
|
|
ResultRelInfo **insert_destrel)
|
|
{
|
|
ModifyTableState *mtstate = context->mtstate;
|
|
EState *estate = context->estate;
|
|
Relation resultRelationDesc;
|
|
List *recheckIndexes = NIL;
|
|
TupleTableSlot *planSlot = context->planSlot;
|
|
TupleTableSlot *result = NULL;
|
|
TransitionCaptureState *ar_insert_trig_tcs;
|
|
ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
|
|
OnConflictAction onconflict = node->onConflictAction;
|
|
PartitionTupleRouting *proute = mtstate->mt_partition_tuple_routing;
|
|
MemoryContext oldContext;
|
|
|
|
/*
|
|
* If the input result relation is a partitioned table, find the leaf
|
|
* partition to insert the tuple into.
|
|
*/
|
|
if (proute)
|
|
{
|
|
ResultRelInfo *partRelInfo;
|
|
|
|
slot = ExecPrepareTupleRouting(mtstate, estate, proute,
|
|
resultRelInfo, slot,
|
|
&partRelInfo);
|
|
resultRelInfo = partRelInfo;
|
|
}
|
|
|
|
ExecMaterializeSlot(slot);
|
|
|
|
resultRelationDesc = resultRelInfo->ri_RelationDesc;
|
|
|
|
/*
|
|
* Open the table's indexes, if we have not done so already, so that we
|
|
* can add new index entries for the inserted tuple.
|
|
*/
|
|
if (resultRelationDesc->rd_rel->relhasindex &&
|
|
resultRelInfo->ri_IndexRelationDescs == NULL)
|
|
ExecOpenIndices(resultRelInfo, onconflict != ONCONFLICT_NONE);
|
|
|
|
/*
|
|
* BEFORE ROW INSERT Triggers.
|
|
*
|
|
* Note: We fire BEFORE ROW TRIGGERS for every attempted insertion in an
|
|
* INSERT ... ON CONFLICT statement. We cannot check for constraint
|
|
* violations before firing these triggers, because they can change the
|
|
* values to insert. Also, they can run arbitrary user-defined code with
|
|
* side-effects that we can't cancel by just not inserting the tuple.
|
|
*/
|
|
if (resultRelInfo->ri_TrigDesc &&
|
|
resultRelInfo->ri_TrigDesc->trig_insert_before_row)
|
|
{
|
|
/* Flush any pending inserts, so rows are visible to the triggers */
|
|
if (estate->es_insert_pending_result_relations != NIL)
|
|
ExecPendingInserts(estate);
|
|
|
|
if (!ExecBRInsertTriggers(estate, resultRelInfo, slot))
|
|
return NULL; /* "do nothing" */
|
|
}
|
|
|
|
/* INSTEAD OF ROW INSERT Triggers */
|
|
if (resultRelInfo->ri_TrigDesc &&
|
|
resultRelInfo->ri_TrigDesc->trig_insert_instead_row)
|
|
{
|
|
if (!ExecIRInsertTriggers(estate, resultRelInfo, slot))
|
|
return NULL; /* "do nothing" */
|
|
}
|
|
else if (resultRelInfo->ri_FdwRoutine)
|
|
{
|
|
/*
|
|
* GENERATED expressions might reference the tableoid column, so
|
|
* (re-)initialize tts_tableOid before evaluating them.
|
|
*/
|
|
slot->tts_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
|
|
|
|
/*
|
|
* Compute stored generated columns
|
|
*/
|
|
if (resultRelationDesc->rd_att->constr &&
|
|
resultRelationDesc->rd_att->constr->has_generated_stored)
|
|
ExecComputeStoredGenerated(resultRelInfo, estate, slot,
|
|
CMD_INSERT);
|
|
|
|
/*
|
|
* If the FDW supports batching, and batching is requested, accumulate
|
|
* rows and insert them in batches. Otherwise use the per-row inserts.
|
|
*/
|
|
if (resultRelInfo->ri_BatchSize > 1)
|
|
{
|
|
bool flushed = false;
|
|
|
|
/*
|
|
* When we've reached the desired batch size, perform the
|
|
* insertion.
|
|
*/
|
|
if (resultRelInfo->ri_NumSlots == resultRelInfo->ri_BatchSize)
|
|
{
|
|
ExecBatchInsert(mtstate, resultRelInfo,
|
|
resultRelInfo->ri_Slots,
|
|
resultRelInfo->ri_PlanSlots,
|
|
resultRelInfo->ri_NumSlots,
|
|
estate, canSetTag);
|
|
flushed = true;
|
|
}
|
|
|
|
oldContext = MemoryContextSwitchTo(estate->es_query_cxt);
|
|
|
|
if (resultRelInfo->ri_Slots == NULL)
|
|
{
|
|
resultRelInfo->ri_Slots = palloc(sizeof(TupleTableSlot *) *
|
|
resultRelInfo->ri_BatchSize);
|
|
resultRelInfo->ri_PlanSlots = palloc(sizeof(TupleTableSlot *) *
|
|
resultRelInfo->ri_BatchSize);
|
|
}
|
|
|
|
/*
|
|
* Initialize the batch slots. We don't know how many slots will
|
|
* be needed, so we initialize them as the batch grows, and we
|
|
* keep them across batches. To mitigate an inefficiency in how
|
|
* resource owner handles objects with many references (as with
|
|
* many slots all referencing the same tuple descriptor) we copy
|
|
* the appropriate tuple descriptor for each slot.
|
|
*/
|
|
if (resultRelInfo->ri_NumSlots >= resultRelInfo->ri_NumSlotsInitialized)
|
|
{
|
|
TupleDesc tdesc = CreateTupleDescCopy(slot->tts_tupleDescriptor);
|
|
TupleDesc plan_tdesc =
|
|
CreateTupleDescCopy(planSlot->tts_tupleDescriptor);
|
|
|
|
resultRelInfo->ri_Slots[resultRelInfo->ri_NumSlots] =
|
|
MakeSingleTupleTableSlot(tdesc, slot->tts_ops);
|
|
|
|
resultRelInfo->ri_PlanSlots[resultRelInfo->ri_NumSlots] =
|
|
MakeSingleTupleTableSlot(plan_tdesc, planSlot->tts_ops);
|
|
|
|
/* remember how many batch slots we initialized */
|
|
resultRelInfo->ri_NumSlotsInitialized++;
|
|
}
|
|
|
|
ExecCopySlot(resultRelInfo->ri_Slots[resultRelInfo->ri_NumSlots],
|
|
slot);
|
|
|
|
ExecCopySlot(resultRelInfo->ri_PlanSlots[resultRelInfo->ri_NumSlots],
|
|
planSlot);
|
|
|
|
/*
|
|
* If these are the first tuples stored in the buffers, add the
|
|
* target rel and the mtstate to the
|
|
* es_insert_pending_result_relations and
|
|
* es_insert_pending_modifytables lists respectively, except in
|
|
* the case where flushing was done above, in which case they
|
|
* would already have been added to the lists, so no need to do
|
|
* this.
|
|
*/
|
|
if (resultRelInfo->ri_NumSlots == 0 && !flushed)
|
|
{
|
|
Assert(!list_member_ptr(estate->es_insert_pending_result_relations,
|
|
resultRelInfo));
|
|
estate->es_insert_pending_result_relations =
|
|
lappend(estate->es_insert_pending_result_relations,
|
|
resultRelInfo);
|
|
estate->es_insert_pending_modifytables =
|
|
lappend(estate->es_insert_pending_modifytables, mtstate);
|
|
}
|
|
Assert(list_member_ptr(estate->es_insert_pending_result_relations,
|
|
resultRelInfo));
|
|
|
|
resultRelInfo->ri_NumSlots++;
|
|
|
|
MemoryContextSwitchTo(oldContext);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* insert into foreign table: let the FDW do it
|
|
*/
|
|
slot = resultRelInfo->ri_FdwRoutine->ExecForeignInsert(estate,
|
|
resultRelInfo,
|
|
slot,
|
|
planSlot);
|
|
|
|
if (slot == NULL) /* "do nothing" */
|
|
return NULL;
|
|
|
|
/*
|
|
* AFTER ROW Triggers or RETURNING expressions might reference the
|
|
* tableoid column, so (re-)initialize tts_tableOid before evaluating
|
|
* them. (This covers the case where the FDW replaced the slot.)
|
|
*/
|
|
slot->tts_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
|
|
}
|
|
else
|
|
{
|
|
WCOKind wco_kind;
|
|
|
|
/*
|
|
* Constraints and GENERATED expressions might reference the tableoid
|
|
* column, so (re-)initialize tts_tableOid before evaluating them.
|
|
*/
|
|
slot->tts_tableOid = RelationGetRelid(resultRelationDesc);
|
|
|
|
/*
|
|
* Compute stored generated columns
|
|
*/
|
|
if (resultRelationDesc->rd_att->constr &&
|
|
resultRelationDesc->rd_att->constr->has_generated_stored)
|
|
ExecComputeStoredGenerated(resultRelInfo, estate, slot,
|
|
CMD_INSERT);
|
|
|
|
/*
|
|
* Check any RLS WITH CHECK policies.
|
|
*
|
|
* Normally we should check INSERT policies. But if the insert is the
|
|
* result of a partition key update that moved the tuple to a new
|
|
* partition, we should instead check UPDATE policies, because we are
|
|
* executing policies defined on the target table, and not those
|
|
* defined on the child partitions.
|
|
*
|
|
* If we're running MERGE, we refer to the action that we're executing
|
|
* to know if we're doing an INSERT or UPDATE to a partition table.
|
|
*/
|
|
if (mtstate->operation == CMD_UPDATE)
|
|
wco_kind = WCO_RLS_UPDATE_CHECK;
|
|
else if (mtstate->operation == CMD_MERGE)
|
|
wco_kind = (context->relaction->mas_action->commandType == CMD_UPDATE) ?
|
|
WCO_RLS_UPDATE_CHECK : WCO_RLS_INSERT_CHECK;
|
|
else
|
|
wco_kind = WCO_RLS_INSERT_CHECK;
|
|
|
|
/*
|
|
* ExecWithCheckOptions() will skip any WCOs which are not of the kind
|
|
* we are looking for at this point.
|
|
*/
|
|
if (resultRelInfo->ri_WithCheckOptions != NIL)
|
|
ExecWithCheckOptions(wco_kind, resultRelInfo, slot, estate);
|
|
|
|
/*
|
|
* Check the constraints of the tuple.
|
|
*/
|
|
if (resultRelationDesc->rd_att->constr)
|
|
ExecConstraints(resultRelInfo, slot, estate);
|
|
|
|
/*
|
|
* Also check the tuple against the partition constraint, if there is
|
|
* one; except that if we got here via tuple-routing, we don't need to
|
|
* if there's no BR trigger defined on the partition.
|
|
*/
|
|
if (resultRelationDesc->rd_rel->relispartition &&
|
|
(resultRelInfo->ri_RootResultRelInfo == NULL ||
|
|
(resultRelInfo->ri_TrigDesc &&
|
|
resultRelInfo->ri_TrigDesc->trig_insert_before_row)))
|
|
ExecPartitionCheck(resultRelInfo, slot, estate, true);
|
|
|
|
if (onconflict != ONCONFLICT_NONE && resultRelInfo->ri_NumIndices > 0)
|
|
{
|
|
/* Perform a speculative insertion. */
|
|
uint32 specToken;
|
|
ItemPointerData conflictTid;
|
|
bool specConflict;
|
|
List *arbiterIndexes;
|
|
|
|
arbiterIndexes = resultRelInfo->ri_onConflictArbiterIndexes;
|
|
|
|
/*
|
|
* Do a non-conclusive check for conflicts first.
|
|
*
|
|
* We're not holding any locks yet, so this doesn't guarantee that
|
|
* the later insert won't conflict. But it avoids leaving behind
|
|
* a lot of canceled speculative insertions, if you run a lot of
|
|
* INSERT ON CONFLICT statements that do conflict.
|
|
*
|
|
* We loop back here if we find a conflict below, either during
|
|
* the pre-check, or when we re-check after inserting the tuple
|
|
* speculatively. Better allow interrupts in case some bug makes
|
|
* this an infinite loop.
|
|
*/
|
|
vlock:
|
|
CHECK_FOR_INTERRUPTS();
|
|
specConflict = false;
|
|
if (!ExecCheckIndexConstraints(resultRelInfo, slot, estate,
|
|
&conflictTid, arbiterIndexes))
|
|
{
|
|
/* committed conflict tuple found */
|
|
if (onconflict == ONCONFLICT_UPDATE)
|
|
{
|
|
/*
|
|
* In case of ON CONFLICT DO UPDATE, execute the UPDATE
|
|
* part. Be prepared to retry if the UPDATE fails because
|
|
* of another concurrent UPDATE/DELETE to the conflict
|
|
* tuple.
|
|
*/
|
|
TupleTableSlot *returning = NULL;
|
|
|
|
if (ExecOnConflictUpdate(context, resultRelInfo,
|
|
&conflictTid, slot, canSetTag,
|
|
&returning))
|
|
{
|
|
InstrCountTuples2(&mtstate->ps, 1);
|
|
return returning;
|
|
}
|
|
else
|
|
goto vlock;
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* In case of ON CONFLICT DO NOTHING, do nothing. However,
|
|
* verify that the tuple is visible to the executor's MVCC
|
|
* snapshot at higher isolation levels.
|
|
*
|
|
* Using ExecGetReturningSlot() to store the tuple for the
|
|
* recheck isn't that pretty, but we can't trivially use
|
|
* the input slot, because it might not be of a compatible
|
|
* type. As there's no conflicting usage of
|
|
* ExecGetReturningSlot() in the DO NOTHING case...
|
|
*/
|
|
Assert(onconflict == ONCONFLICT_NOTHING);
|
|
ExecCheckTIDVisible(estate, resultRelInfo, &conflictTid,
|
|
ExecGetReturningSlot(estate, resultRelInfo));
|
|
InstrCountTuples2(&mtstate->ps, 1);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Before we start insertion proper, acquire our "speculative
|
|
* insertion lock". Others can use that to wait for us to decide
|
|
* if we're going to go ahead with the insertion, instead of
|
|
* waiting for the whole transaction to complete.
|
|
*/
|
|
specToken = SpeculativeInsertionLockAcquire(GetCurrentTransactionId());
|
|
|
|
/* insert the tuple, with the speculative token */
|
|
table_tuple_insert_speculative(resultRelationDesc, slot,
|
|
estate->es_output_cid,
|
|
0,
|
|
NULL,
|
|
specToken);
|
|
|
|
/* insert index entries for tuple */
|
|
recheckIndexes = ExecInsertIndexTuples(resultRelInfo,
|
|
slot, estate, false, true,
|
|
&specConflict,
|
|
arbiterIndexes,
|
|
false);
|
|
|
|
/* adjust the tuple's state accordingly */
|
|
table_tuple_complete_speculative(resultRelationDesc, slot,
|
|
specToken, !specConflict);
|
|
|
|
/*
|
|
* Wake up anyone waiting for our decision. They will re-check
|
|
* the tuple, see that it's no longer speculative, and wait on our
|
|
* XID as if this was a regularly inserted tuple all along. Or if
|
|
* we killed the tuple, they will see it's dead, and proceed as if
|
|
* the tuple never existed.
|
|
*/
|
|
SpeculativeInsertionLockRelease(GetCurrentTransactionId());
|
|
|
|
/*
|
|
* If there was a conflict, start from the beginning. We'll do
|
|
* the pre-check again, which will now find the conflicting tuple
|
|
* (unless it aborts before we get there).
|
|
*/
|
|
if (specConflict)
|
|
{
|
|
list_free(recheckIndexes);
|
|
goto vlock;
|
|
}
|
|
|
|
/* Since there was no insertion conflict, we're done */
|
|
}
|
|
else
|
|
{
|
|
/* insert the tuple normally */
|
|
table_tuple_insert(resultRelationDesc, slot,
|
|
estate->es_output_cid,
|
|
0, NULL);
|
|
|
|
/* insert index entries for tuple */
|
|
if (resultRelInfo->ri_NumIndices > 0)
|
|
recheckIndexes = ExecInsertIndexTuples(resultRelInfo,
|
|
slot, estate, false,
|
|
false, NULL, NIL,
|
|
false);
|
|
}
|
|
}
|
|
|
|
if (canSetTag)
|
|
(estate->es_processed)++;
|
|
|
|
/*
|
|
* If this insert is the result of a partition key update that moved the
|
|
* tuple to a new partition, put this row into the transition NEW TABLE,
|
|
* if there is one. We need to do this separately for DELETE and INSERT
|
|
* because they happen on different tables.
|
|
*/
|
|
ar_insert_trig_tcs = mtstate->mt_transition_capture;
|
|
if (mtstate->operation == CMD_UPDATE && mtstate->mt_transition_capture
|
|
&& mtstate->mt_transition_capture->tcs_update_new_table)
|
|
{
|
|
ExecARUpdateTriggers(estate, resultRelInfo,
|
|
NULL, NULL,
|
|
NULL,
|
|
NULL,
|
|
slot,
|
|
NULL,
|
|
mtstate->mt_transition_capture,
|
|
false);
|
|
|
|
/*
|
|
* We've already captured the NEW TABLE row, so make sure any AR
|
|
* INSERT trigger fired below doesn't capture it again.
|
|
*/
|
|
ar_insert_trig_tcs = NULL;
|
|
}
|
|
|
|
/* AFTER ROW INSERT Triggers */
|
|
ExecARInsertTriggers(estate, resultRelInfo, slot, recheckIndexes,
|
|
ar_insert_trig_tcs);
|
|
|
|
list_free(recheckIndexes);
|
|
|
|
/*
|
|
* Check any WITH CHECK OPTION constraints from parent views. We are
|
|
* required to do this after testing all constraints and uniqueness
|
|
* violations per the SQL spec, so we do it after actually inserting the
|
|
* record into the heap and all indexes.
|
|
*
|
|
* ExecWithCheckOptions will elog(ERROR) if a violation is found, so the
|
|
* tuple will never be seen, if it violates the WITH CHECK OPTION.
|
|
*
|
|
* ExecWithCheckOptions() will skip any WCOs which are not of the kind we
|
|
* are looking for at this point.
|
|
*/
|
|
if (resultRelInfo->ri_WithCheckOptions != NIL)
|
|
ExecWithCheckOptions(WCO_VIEW_CHECK, resultRelInfo, slot, estate);
|
|
|
|
/* Process RETURNING if present */
|
|
if (resultRelInfo->ri_projectReturning)
|
|
result = ExecProcessReturning(resultRelInfo, slot, planSlot);
|
|
|
|
if (inserted_tuple)
|
|
*inserted_tuple = slot;
|
|
if (insert_destrel)
|
|
*insert_destrel = resultRelInfo;
|
|
|
|
return result;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecBatchInsert
|
|
*
|
|
* Insert multiple tuples in an efficient way.
|
|
* Currently, this handles inserting into a foreign table without
|
|
* RETURNING clause.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static void
|
|
ExecBatchInsert(ModifyTableState *mtstate,
|
|
ResultRelInfo *resultRelInfo,
|
|
TupleTableSlot **slots,
|
|
TupleTableSlot **planSlots,
|
|
int numSlots,
|
|
EState *estate,
|
|
bool canSetTag)
|
|
{
|
|
int i;
|
|
int numInserted = numSlots;
|
|
TupleTableSlot *slot = NULL;
|
|
TupleTableSlot **rslots;
|
|
|
|
/*
|
|
* insert into foreign table: let the FDW do it
|
|
*/
|
|
rslots = resultRelInfo->ri_FdwRoutine->ExecForeignBatchInsert(estate,
|
|
resultRelInfo,
|
|
slots,
|
|
planSlots,
|
|
&numInserted);
|
|
|
|
for (i = 0; i < numInserted; i++)
|
|
{
|
|
slot = rslots[i];
|
|
|
|
/*
|
|
* AFTER ROW Triggers might reference the tableoid column, so
|
|
* (re-)initialize tts_tableOid before evaluating them.
|
|
*/
|
|
slot->tts_tableOid = RelationGetRelid(resultRelInfo->ri_RelationDesc);
|
|
|
|
/* AFTER ROW INSERT Triggers */
|
|
ExecARInsertTriggers(estate, resultRelInfo, slot, NIL,
|
|
mtstate->mt_transition_capture);
|
|
|
|
/*
|
|
* Check any WITH CHECK OPTION constraints from parent views. See the
|
|
* comment in ExecInsert.
|
|
*/
|
|
if (resultRelInfo->ri_WithCheckOptions != NIL)
|
|
ExecWithCheckOptions(WCO_VIEW_CHECK, resultRelInfo, slot, estate);
|
|
}
|
|
|
|
if (canSetTag && numInserted > 0)
|
|
estate->es_processed += numInserted;
|
|
|
|
/* Clean up all the slots, ready for the next batch */
|
|
for (i = 0; i < numSlots; i++)
|
|
{
|
|
ExecClearTuple(slots[i]);
|
|
ExecClearTuple(planSlots[i]);
|
|
}
|
|
resultRelInfo->ri_NumSlots = 0;
|
|
}
|
|
|
|
/*
|
|
* ExecPendingInserts -- flushes all pending inserts to the foreign tables
|
|
*/
|
|
static void
|
|
ExecPendingInserts(EState *estate)
|
|
{
|
|
ListCell *l1,
|
|
*l2;
|
|
|
|
forboth(l1, estate->es_insert_pending_result_relations,
|
|
l2, estate->es_insert_pending_modifytables)
|
|
{
|
|
ResultRelInfo *resultRelInfo = (ResultRelInfo *) lfirst(l1);
|
|
ModifyTableState *mtstate = (ModifyTableState *) lfirst(l2);
|
|
|
|
Assert(mtstate);
|
|
ExecBatchInsert(mtstate, resultRelInfo,
|
|
resultRelInfo->ri_Slots,
|
|
resultRelInfo->ri_PlanSlots,
|
|
resultRelInfo->ri_NumSlots,
|
|
estate, mtstate->canSetTag);
|
|
}
|
|
|
|
list_free(estate->es_insert_pending_result_relations);
|
|
list_free(estate->es_insert_pending_modifytables);
|
|
estate->es_insert_pending_result_relations = NIL;
|
|
estate->es_insert_pending_modifytables = NIL;
|
|
}
|
|
|
|
/*
|
|
* ExecDeletePrologue -- subroutine for ExecDelete
|
|
*
|
|
* Prepare executor state for DELETE. Actually, the only thing we have to do
|
|
* here is execute BEFORE ROW triggers. We return false if one of them makes
|
|
* the delete a no-op; otherwise, return true.
|
|
*/
|
|
static bool
|
|
ExecDeletePrologue(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
|
|
ItemPointer tupleid, HeapTuple oldtuple,
|
|
TupleTableSlot **epqreturnslot, TM_Result *result)
|
|
{
|
|
if (result)
|
|
*result = TM_Ok;
|
|
|
|
/* BEFORE ROW DELETE triggers */
|
|
if (resultRelInfo->ri_TrigDesc &&
|
|
resultRelInfo->ri_TrigDesc->trig_delete_before_row)
|
|
{
|
|
/* Flush any pending inserts, so rows are visible to the triggers */
|
|
if (context->estate->es_insert_pending_result_relations != NIL)
|
|
ExecPendingInserts(context->estate);
|
|
|
|
return ExecBRDeleteTriggers(context->estate, context->epqstate,
|
|
resultRelInfo, tupleid, oldtuple,
|
|
epqreturnslot, result, &context->tmfd);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* ExecDeleteAct -- subroutine for ExecDelete
|
|
*
|
|
* Actually delete the tuple from a plain table.
|
|
*
|
|
* Caller is in charge of doing EvalPlanQual as necessary
|
|
*/
|
|
static TM_Result
|
|
ExecDeleteAct(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
|
|
ItemPointer tupleid, bool changingPart)
|
|
{
|
|
EState *estate = context->estate;
|
|
|
|
return table_tuple_delete(resultRelInfo->ri_RelationDesc, tupleid,
|
|
estate->es_output_cid,
|
|
estate->es_snapshot,
|
|
estate->es_crosscheck_snapshot,
|
|
true /* wait for commit */ ,
|
|
&context->tmfd,
|
|
changingPart);
|
|
}
|
|
|
|
/*
|
|
* ExecDeleteEpilogue -- subroutine for ExecDelete
|
|
*
|
|
* Closing steps of tuple deletion; this invokes AFTER FOR EACH ROW triggers,
|
|
* including the UPDATE triggers if the deletion is being done as part of a
|
|
* cross-partition tuple move.
|
|
*/
|
|
static void
|
|
ExecDeleteEpilogue(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
|
|
ItemPointer tupleid, HeapTuple oldtuple, bool changingPart)
|
|
{
|
|
ModifyTableState *mtstate = context->mtstate;
|
|
EState *estate = context->estate;
|
|
TransitionCaptureState *ar_delete_trig_tcs;
|
|
|
|
/*
|
|
* If this delete is the result of a partition key update that moved the
|
|
* tuple to a new partition, put this row into the transition OLD TABLE,
|
|
* if there is one. We need to do this separately for DELETE and INSERT
|
|
* because they happen on different tables.
|
|
*/
|
|
ar_delete_trig_tcs = mtstate->mt_transition_capture;
|
|
if (mtstate->operation == CMD_UPDATE && mtstate->mt_transition_capture &&
|
|
mtstate->mt_transition_capture->tcs_update_old_table)
|
|
{
|
|
ExecARUpdateTriggers(estate, resultRelInfo,
|
|
NULL, NULL,
|
|
tupleid, oldtuple,
|
|
NULL, NULL, mtstate->mt_transition_capture,
|
|
false);
|
|
|
|
/*
|
|
* We've already captured the OLD TABLE row, so make sure any AR
|
|
* DELETE trigger fired below doesn't capture it again.
|
|
*/
|
|
ar_delete_trig_tcs = NULL;
|
|
}
|
|
|
|
/* AFTER ROW DELETE Triggers */
|
|
ExecARDeleteTriggers(estate, resultRelInfo, tupleid, oldtuple,
|
|
ar_delete_trig_tcs, changingPart);
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecDelete
|
|
*
|
|
* DELETE is like UPDATE, except that we delete the tuple and no
|
|
* index modifications are needed.
|
|
*
|
|
* When deleting from a table, tupleid identifies the tuple to
|
|
* delete and oldtuple is NULL. When deleting from a view,
|
|
* oldtuple is passed to the INSTEAD OF triggers and identifies
|
|
* what to delete, and tupleid is invalid. When deleting from a
|
|
* foreign table, tupleid is invalid; the FDW has to figure out
|
|
* which row to delete using data from the planSlot. oldtuple is
|
|
* passed to foreign table triggers; it is NULL when the foreign
|
|
* table has no relevant triggers. We use tupleDeleted to indicate
|
|
* whether the tuple is actually deleted, callers can use it to
|
|
* decide whether to continue the operation. When this DELETE is a
|
|
* part of an UPDATE of partition-key, then the slot returned by
|
|
* EvalPlanQual() is passed back using output parameter epqreturnslot.
|
|
*
|
|
* Returns RETURNING result if any, otherwise NULL.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static TupleTableSlot *
|
|
ExecDelete(ModifyTableContext *context,
|
|
ResultRelInfo *resultRelInfo,
|
|
ItemPointer tupleid,
|
|
HeapTuple oldtuple,
|
|
bool processReturning,
|
|
bool changingPart,
|
|
bool canSetTag,
|
|
TM_Result *tmresult,
|
|
bool *tupleDeleted,
|
|
TupleTableSlot **epqreturnslot)
|
|
{
|
|
EState *estate = context->estate;
|
|
Relation resultRelationDesc = resultRelInfo->ri_RelationDesc;
|
|
TupleTableSlot *slot = NULL;
|
|
TM_Result result;
|
|
|
|
if (tupleDeleted)
|
|
*tupleDeleted = false;
|
|
|
|
/*
|
|
* Prepare for the delete. This includes BEFORE ROW triggers, so we're
|
|
* done if it says we are.
|
|
*/
|
|
if (!ExecDeletePrologue(context, resultRelInfo, tupleid, oldtuple,
|
|
epqreturnslot, tmresult))
|
|
return NULL;
|
|
|
|
/* INSTEAD OF ROW DELETE Triggers */
|
|
if (resultRelInfo->ri_TrigDesc &&
|
|
resultRelInfo->ri_TrigDesc->trig_delete_instead_row)
|
|
{
|
|
bool dodelete;
|
|
|
|
Assert(oldtuple != NULL);
|
|
dodelete = ExecIRDeleteTriggers(estate, resultRelInfo, oldtuple);
|
|
|
|
if (!dodelete) /* "do nothing" */
|
|
return NULL;
|
|
}
|
|
else if (resultRelInfo->ri_FdwRoutine)
|
|
{
|
|
/*
|
|
* delete from foreign table: let the FDW do it
|
|
*
|
|
* We offer the returning slot as a place to store RETURNING data,
|
|
* although the FDW can return some other slot if it wants.
|
|
*/
|
|
slot = ExecGetReturningSlot(estate, resultRelInfo);
|
|
slot = resultRelInfo->ri_FdwRoutine->ExecForeignDelete(estate,
|
|
resultRelInfo,
|
|
slot,
|
|
context->planSlot);
|
|
|
|
if (slot == NULL) /* "do nothing" */
|
|
return NULL;
|
|
|
|
/*
|
|
* RETURNING expressions might reference the tableoid column, so
|
|
* (re)initialize tts_tableOid before evaluating them.
|
|
*/
|
|
if (TTS_EMPTY(slot))
|
|
ExecStoreAllNullTuple(slot);
|
|
|
|
slot->tts_tableOid = RelationGetRelid(resultRelationDesc);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* delete the tuple
|
|
*
|
|
* Note: if context->estate->es_crosscheck_snapshot isn't
|
|
* InvalidSnapshot, we check that the row to be deleted is visible to
|
|
* that snapshot, and throw a can't-serialize error if not. This is a
|
|
* special-case behavior needed for referential integrity updates in
|
|
* transaction-snapshot mode transactions.
|
|
*/
|
|
ldelete:
|
|
result = ExecDeleteAct(context, resultRelInfo, tupleid, changingPart);
|
|
|
|
if (tmresult)
|
|
*tmresult = result;
|
|
|
|
switch (result)
|
|
{
|
|
case TM_SelfModified:
|
|
|
|
/*
|
|
* The target tuple was already updated or deleted by the
|
|
* current command, or by a later command in the current
|
|
* transaction. The former case is possible in a join DELETE
|
|
* where multiple tuples join to the same target tuple. This
|
|
* is somewhat questionable, but Postgres has always allowed
|
|
* it: we just ignore additional deletion attempts.
|
|
*
|
|
* The latter case arises if the tuple is modified by a
|
|
* command in a BEFORE trigger, or perhaps by a command in a
|
|
* volatile function used in the query. In such situations we
|
|
* should not ignore the deletion, but it is equally unsafe to
|
|
* proceed. We don't want to discard the original DELETE
|
|
* while keeping the triggered actions based on its deletion;
|
|
* and it would be no better to allow the original DELETE
|
|
* while discarding updates that it triggered. The row update
|
|
* carries some information that might be important according
|
|
* to business rules; so throwing an error is the only safe
|
|
* course.
|
|
*
|
|
* If a trigger actually intends this type of interaction, it
|
|
* can re-execute the DELETE and then return NULL to cancel
|
|
* the outer delete.
|
|
*/
|
|
if (context->tmfd.cmax != estate->es_output_cid)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
|
|
errmsg("tuple to be deleted was already modified by an operation triggered by the current command"),
|
|
errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
|
|
|
|
/* Else, already deleted by self; nothing to do */
|
|
return NULL;
|
|
|
|
case TM_Ok:
|
|
break;
|
|
|
|
case TM_Updated:
|
|
{
|
|
TupleTableSlot *inputslot;
|
|
TupleTableSlot *epqslot;
|
|
|
|
if (IsolationUsesXactSnapshot())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("could not serialize access due to concurrent update")));
|
|
|
|
/*
|
|
* Already know that we're going to need to do EPQ, so
|
|
* fetch tuple directly into the right slot.
|
|
*/
|
|
EvalPlanQualBegin(context->epqstate);
|
|
inputslot = EvalPlanQualSlot(context->epqstate, resultRelationDesc,
|
|
resultRelInfo->ri_RangeTableIndex);
|
|
|
|
result = table_tuple_lock(resultRelationDesc, tupleid,
|
|
estate->es_snapshot,
|
|
inputslot, estate->es_output_cid,
|
|
LockTupleExclusive, LockWaitBlock,
|
|
TUPLE_LOCK_FLAG_FIND_LAST_VERSION,
|
|
&context->tmfd);
|
|
|
|
switch (result)
|
|
{
|
|
case TM_Ok:
|
|
Assert(context->tmfd.traversed);
|
|
epqslot = EvalPlanQual(context->epqstate,
|
|
resultRelationDesc,
|
|
resultRelInfo->ri_RangeTableIndex,
|
|
inputslot);
|
|
if (TupIsNull(epqslot))
|
|
/* Tuple not passing quals anymore, exiting... */
|
|
return NULL;
|
|
|
|
/*
|
|
* If requested, skip delete and pass back the
|
|
* updated row.
|
|
*/
|
|
if (epqreturnslot)
|
|
{
|
|
*epqreturnslot = epqslot;
|
|
return NULL;
|
|
}
|
|
else
|
|
goto ldelete;
|
|
|
|
case TM_SelfModified:
|
|
|
|
/*
|
|
* This can be reached when following an update
|
|
* chain from a tuple updated by another session,
|
|
* reaching a tuple that was already updated in
|
|
* this transaction. If previously updated by this
|
|
* command, ignore the delete, otherwise error
|
|
* out.
|
|
*
|
|
* See also TM_SelfModified response to
|
|
* table_tuple_delete() above.
|
|
*/
|
|
if (context->tmfd.cmax != estate->es_output_cid)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
|
|
errmsg("tuple to be deleted was already modified by an operation triggered by the current command"),
|
|
errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
|
|
return NULL;
|
|
|
|
case TM_Deleted:
|
|
/* tuple already deleted; nothing to do */
|
|
return NULL;
|
|
|
|
default:
|
|
|
|
/*
|
|
* TM_Invisible should be impossible because we're
|
|
* waiting for updated row versions, and would
|
|
* already have errored out if the first version
|
|
* is invisible.
|
|
*
|
|
* TM_Updated should be impossible, because we're
|
|
* locking the latest version via
|
|
* TUPLE_LOCK_FLAG_FIND_LAST_VERSION.
|
|
*/
|
|
elog(ERROR, "unexpected table_tuple_lock status: %u",
|
|
result);
|
|
return NULL;
|
|
}
|
|
|
|
Assert(false);
|
|
break;
|
|
}
|
|
|
|
case TM_Deleted:
|
|
if (IsolationUsesXactSnapshot())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("could not serialize access due to concurrent delete")));
|
|
/* tuple already deleted; nothing to do */
|
|
return NULL;
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized table_tuple_delete status: %u",
|
|
result);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Note: Normally one would think that we have to delete index tuples
|
|
* associated with the heap tuple now...
|
|
*
|
|
* ... but in POSTGRES, we have no need to do this because VACUUM will
|
|
* take care of it later. We can't delete index tuples immediately
|
|
* anyway, since the tuple is still visible to other transactions.
|
|
*/
|
|
}
|
|
|
|
if (canSetTag)
|
|
(estate->es_processed)++;
|
|
|
|
/* Tell caller that the delete actually happened. */
|
|
if (tupleDeleted)
|
|
*tupleDeleted = true;
|
|
|
|
ExecDeleteEpilogue(context, resultRelInfo, tupleid, oldtuple, changingPart);
|
|
|
|
/* Process RETURNING if present and if requested */
|
|
if (processReturning && resultRelInfo->ri_projectReturning)
|
|
{
|
|
/*
|
|
* We have to put the target tuple into a slot, which means first we
|
|
* gotta fetch it. We can use the trigger tuple slot.
|
|
*/
|
|
TupleTableSlot *rslot;
|
|
|
|
if (resultRelInfo->ri_FdwRoutine)
|
|
{
|
|
/* FDW must have provided a slot containing the deleted row */
|
|
Assert(!TupIsNull(slot));
|
|
}
|
|
else
|
|
{
|
|
slot = ExecGetReturningSlot(estate, resultRelInfo);
|
|
if (oldtuple != NULL)
|
|
{
|
|
ExecForceStoreHeapTuple(oldtuple, slot, false);
|
|
}
|
|
else
|
|
{
|
|
if (!table_tuple_fetch_row_version(resultRelationDesc, tupleid,
|
|
SnapshotAny, slot))
|
|
elog(ERROR, "failed to fetch deleted tuple for DELETE RETURNING");
|
|
}
|
|
}
|
|
|
|
rslot = ExecProcessReturning(resultRelInfo, slot, context->planSlot);
|
|
|
|
/*
|
|
* Before releasing the target tuple again, make sure rslot has a
|
|
* local copy of any pass-by-reference values.
|
|
*/
|
|
ExecMaterializeSlot(rslot);
|
|
|
|
ExecClearTuple(slot);
|
|
|
|
return rslot;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* ExecCrossPartitionUpdate --- Move an updated tuple to another partition.
|
|
*
|
|
* This works by first deleting the old tuple from the current partition,
|
|
* followed by inserting the new tuple into the root parent table, that is,
|
|
* mtstate->rootResultRelInfo. It will be re-routed from there to the
|
|
* correct partition.
|
|
*
|
|
* Returns true if the tuple has been successfully moved, or if it's found
|
|
* that the tuple was concurrently deleted so there's nothing more to do
|
|
* for the caller.
|
|
*
|
|
* False is returned if the tuple we're trying to move is found to have been
|
|
* concurrently updated. In that case, the caller must check if the updated
|
|
* tuple that's returned in *retry_slot still needs to be re-routed, and call
|
|
* this function again or perform a regular update accordingly. For MERGE,
|
|
* the updated tuple is not returned in *retry_slot; it has its own retry
|
|
* logic.
|
|
*/
|
|
static bool
|
|
ExecCrossPartitionUpdate(ModifyTableContext *context,
|
|
ResultRelInfo *resultRelInfo,
|
|
ItemPointer tupleid, HeapTuple oldtuple,
|
|
TupleTableSlot *slot,
|
|
bool canSetTag,
|
|
UpdateContext *updateCxt,
|
|
TM_Result *tmresult,
|
|
TupleTableSlot **retry_slot,
|
|
TupleTableSlot **inserted_tuple,
|
|
ResultRelInfo **insert_destrel)
|
|
{
|
|
ModifyTableState *mtstate = context->mtstate;
|
|
EState *estate = mtstate->ps.state;
|
|
TupleConversionMap *tupconv_map;
|
|
bool tuple_deleted;
|
|
TupleTableSlot *epqslot = NULL;
|
|
|
|
context->cpUpdateReturningSlot = NULL;
|
|
*retry_slot = NULL;
|
|
|
|
/*
|
|
* Disallow an INSERT ON CONFLICT DO UPDATE that causes the original row
|
|
* to migrate to a different partition. Maybe this can be implemented
|
|
* some day, but it seems a fringe feature with little redeeming value.
|
|
*/
|
|
if (((ModifyTable *) mtstate->ps.plan)->onConflictAction == ONCONFLICT_UPDATE)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("invalid ON UPDATE specification"),
|
|
errdetail("The result tuple would appear in a different partition than the original tuple.")));
|
|
|
|
/*
|
|
* When an UPDATE is run directly on a leaf partition, simply fail with a
|
|
* partition constraint violation error.
|
|
*/
|
|
if (resultRelInfo == mtstate->rootResultRelInfo)
|
|
ExecPartitionCheckEmitError(resultRelInfo, slot, estate);
|
|
|
|
/* Initialize tuple routing info if not already done. */
|
|
if (mtstate->mt_partition_tuple_routing == NULL)
|
|
{
|
|
Relation rootRel = mtstate->rootResultRelInfo->ri_RelationDesc;
|
|
MemoryContext oldcxt;
|
|
|
|
/* Things built here have to last for the query duration. */
|
|
oldcxt = MemoryContextSwitchTo(estate->es_query_cxt);
|
|
|
|
mtstate->mt_partition_tuple_routing =
|
|
ExecSetupPartitionTupleRouting(estate, rootRel);
|
|
|
|
/*
|
|
* Before a partition's tuple can be re-routed, it must first be
|
|
* converted to the root's format, so we'll need a slot for storing
|
|
* such tuples.
|
|
*/
|
|
Assert(mtstate->mt_root_tuple_slot == NULL);
|
|
mtstate->mt_root_tuple_slot = table_slot_create(rootRel, NULL);
|
|
|
|
MemoryContextSwitchTo(oldcxt);
|
|
}
|
|
|
|
/*
|
|
* Row movement, part 1. Delete the tuple, but skip RETURNING processing.
|
|
* We want to return rows from INSERT.
|
|
*/
|
|
ExecDelete(context, resultRelInfo,
|
|
tupleid, oldtuple,
|
|
false, /* processReturning */
|
|
true, /* changingPart */
|
|
false, /* canSetTag */
|
|
tmresult, &tuple_deleted, &epqslot);
|
|
|
|
/*
|
|
* For some reason if DELETE didn't happen (e.g. trigger prevented it, or
|
|
* it was already deleted by self, or it was concurrently deleted by
|
|
* another transaction), then we should skip the insert as well;
|
|
* otherwise, an UPDATE could cause an increase in the total number of
|
|
* rows across all partitions, which is clearly wrong.
|
|
*
|
|
* For a normal UPDATE, the case where the tuple has been the subject of a
|
|
* concurrent UPDATE or DELETE would be handled by the EvalPlanQual
|
|
* machinery, but for an UPDATE that we've translated into a DELETE from
|
|
* this partition and an INSERT into some other partition, that's not
|
|
* available, because CTID chains can't span relation boundaries. We
|
|
* mimic the semantics to a limited extent by skipping the INSERT if the
|
|
* DELETE fails to find a tuple. This ensures that two concurrent
|
|
* attempts to UPDATE the same tuple at the same time can't turn one tuple
|
|
* into two, and that an UPDATE of a just-deleted tuple can't resurrect
|
|
* it.
|
|
*/
|
|
if (!tuple_deleted)
|
|
{
|
|
/*
|
|
* epqslot will be typically NULL. But when ExecDelete() finds that
|
|
* another transaction has concurrently updated the same row, it
|
|
* re-fetches the row, skips the delete, and epqslot is set to the
|
|
* re-fetched tuple slot. In that case, we need to do all the checks
|
|
* again. For MERGE, we leave everything to the caller (it must do
|
|
* additional rechecking, and might end up executing a different
|
|
* action entirely).
|
|
*/
|
|
if (context->relaction != NULL)
|
|
return *tmresult == TM_Ok;
|
|
else if (TupIsNull(epqslot))
|
|
return true;
|
|
else
|
|
{
|
|
/* Fetch the most recent version of old tuple. */
|
|
TupleTableSlot *oldSlot;
|
|
|
|
/* ... but first, make sure ri_oldTupleSlot is initialized. */
|
|
if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
|
|
ExecInitUpdateProjection(mtstate, resultRelInfo);
|
|
oldSlot = resultRelInfo->ri_oldTupleSlot;
|
|
if (!table_tuple_fetch_row_version(resultRelInfo->ri_RelationDesc,
|
|
tupleid,
|
|
SnapshotAny,
|
|
oldSlot))
|
|
elog(ERROR, "failed to fetch tuple being updated");
|
|
/* and project the new tuple to retry the UPDATE with */
|
|
*retry_slot = ExecGetUpdateNewTuple(resultRelInfo, epqslot,
|
|
oldSlot);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* resultRelInfo is one of the per-relation resultRelInfos. So we should
|
|
* convert the tuple into root's tuple descriptor if needed, since
|
|
* ExecInsert() starts the search from root.
|
|
*/
|
|
tupconv_map = ExecGetChildToRootMap(resultRelInfo);
|
|
if (tupconv_map != NULL)
|
|
slot = execute_attr_map_slot(tupconv_map->attrMap,
|
|
slot,
|
|
mtstate->mt_root_tuple_slot);
|
|
|
|
/* Tuple routing starts from the root table. */
|
|
context->cpUpdateReturningSlot =
|
|
ExecInsert(context, mtstate->rootResultRelInfo, slot, canSetTag,
|
|
inserted_tuple, insert_destrel);
|
|
|
|
/*
|
|
* Reset the transition state that may possibly have been written by
|
|
* INSERT.
|
|
*/
|
|
if (mtstate->mt_transition_capture)
|
|
mtstate->mt_transition_capture->tcs_original_insert_tuple = NULL;
|
|
|
|
/* We're done moving. */
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* ExecUpdatePrologue -- subroutine for ExecUpdate
|
|
*
|
|
* Prepare executor state for UPDATE. This includes running BEFORE ROW
|
|
* triggers. We return false if one of them makes the update a no-op;
|
|
* otherwise, return true.
|
|
*/
|
|
static bool
|
|
ExecUpdatePrologue(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
|
|
ItemPointer tupleid, HeapTuple oldtuple, TupleTableSlot *slot,
|
|
TM_Result *result)
|
|
{
|
|
Relation resultRelationDesc = resultRelInfo->ri_RelationDesc;
|
|
|
|
if (result)
|
|
*result = TM_Ok;
|
|
|
|
ExecMaterializeSlot(slot);
|
|
|
|
/*
|
|
* Open the table's indexes, if we have not done so already, so that we
|
|
* can add new index entries for the updated tuple.
|
|
*/
|
|
if (resultRelationDesc->rd_rel->relhasindex &&
|
|
resultRelInfo->ri_IndexRelationDescs == NULL)
|
|
ExecOpenIndices(resultRelInfo, false);
|
|
|
|
/* BEFORE ROW UPDATE triggers */
|
|
if (resultRelInfo->ri_TrigDesc &&
|
|
resultRelInfo->ri_TrigDesc->trig_update_before_row)
|
|
{
|
|
/* Flush any pending inserts, so rows are visible to the triggers */
|
|
if (context->estate->es_insert_pending_result_relations != NIL)
|
|
ExecPendingInserts(context->estate);
|
|
|
|
return ExecBRUpdateTriggers(context->estate, context->epqstate,
|
|
resultRelInfo, tupleid, oldtuple, slot,
|
|
result, &context->tmfd);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* ExecUpdatePrepareSlot -- subroutine for ExecUpdateAct
|
|
*
|
|
* Apply the final modifications to the tuple slot before the update.
|
|
* (This is split out because we also need it in the foreign-table code path.)
|
|
*/
|
|
static void
|
|
ExecUpdatePrepareSlot(ResultRelInfo *resultRelInfo,
|
|
TupleTableSlot *slot,
|
|
EState *estate)
|
|
{
|
|
Relation resultRelationDesc = resultRelInfo->ri_RelationDesc;
|
|
|
|
/*
|
|
* Constraints and GENERATED expressions might reference the tableoid
|
|
* column, so (re-)initialize tts_tableOid before evaluating them.
|
|
*/
|
|
slot->tts_tableOid = RelationGetRelid(resultRelationDesc);
|
|
|
|
/*
|
|
* Compute stored generated columns
|
|
*/
|
|
if (resultRelationDesc->rd_att->constr &&
|
|
resultRelationDesc->rd_att->constr->has_generated_stored)
|
|
ExecComputeStoredGenerated(resultRelInfo, estate, slot,
|
|
CMD_UPDATE);
|
|
}
|
|
|
|
/*
|
|
* ExecUpdateAct -- subroutine for ExecUpdate
|
|
*
|
|
* Actually update the tuple, when operating on a plain table. If the
|
|
* table is a partition, and the command was called referencing an ancestor
|
|
* partitioned table, this routine migrates the resulting tuple to another
|
|
* partition.
|
|
*
|
|
* The caller is in charge of keeping indexes current as necessary. The
|
|
* caller is also in charge of doing EvalPlanQual if the tuple is found to
|
|
* be concurrently updated. However, in case of a cross-partition update,
|
|
* this routine does it.
|
|
*/
|
|
static TM_Result
|
|
ExecUpdateAct(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
|
|
ItemPointer tupleid, HeapTuple oldtuple, TupleTableSlot *slot,
|
|
bool canSetTag, UpdateContext *updateCxt)
|
|
{
|
|
EState *estate = context->estate;
|
|
Relation resultRelationDesc = resultRelInfo->ri_RelationDesc;
|
|
bool partition_constraint_failed;
|
|
TM_Result result;
|
|
|
|
updateCxt->crossPartUpdate = false;
|
|
|
|
/*
|
|
* If we move the tuple to a new partition, we loop back here to recompute
|
|
* GENERATED values (which are allowed to be different across partitions)
|
|
* and recheck any RLS policies and constraints. We do not fire any
|
|
* BEFORE triggers of the new partition, however.
|
|
*/
|
|
lreplace:
|
|
/* Fill in GENERATEd columns */
|
|
ExecUpdatePrepareSlot(resultRelInfo, slot, estate);
|
|
|
|
/* ensure slot is independent, consider e.g. EPQ */
|
|
ExecMaterializeSlot(slot);
|
|
|
|
/*
|
|
* If partition constraint fails, this row might get moved to another
|
|
* partition, in which case we should check the RLS CHECK policy just
|
|
* before inserting into the new partition, rather than doing it here.
|
|
* This is because a trigger on that partition might again change the row.
|
|
* So skip the WCO checks if the partition constraint fails.
|
|
*/
|
|
partition_constraint_failed =
|
|
resultRelationDesc->rd_rel->relispartition &&
|
|
!ExecPartitionCheck(resultRelInfo, slot, estate, false);
|
|
|
|
/* Check any RLS UPDATE WITH CHECK policies */
|
|
if (!partition_constraint_failed &&
|
|
resultRelInfo->ri_WithCheckOptions != NIL)
|
|
{
|
|
/*
|
|
* ExecWithCheckOptions() will skip any WCOs which are not of the kind
|
|
* we are looking for at this point.
|
|
*/
|
|
ExecWithCheckOptions(WCO_RLS_UPDATE_CHECK,
|
|
resultRelInfo, slot, estate);
|
|
}
|
|
|
|
/*
|
|
* If a partition check failed, try to move the row into the right
|
|
* partition.
|
|
*/
|
|
if (partition_constraint_failed)
|
|
{
|
|
TupleTableSlot *inserted_tuple,
|
|
*retry_slot;
|
|
ResultRelInfo *insert_destrel = NULL;
|
|
|
|
/*
|
|
* ExecCrossPartitionUpdate will first DELETE the row from the
|
|
* partition it's currently in and then insert it back into the root
|
|
* table, which will re-route it to the correct partition. However,
|
|
* if the tuple has been concurrently updated, a retry is needed.
|
|
*/
|
|
if (ExecCrossPartitionUpdate(context, resultRelInfo,
|
|
tupleid, oldtuple, slot,
|
|
canSetTag, updateCxt,
|
|
&result,
|
|
&retry_slot,
|
|
&inserted_tuple,
|
|
&insert_destrel))
|
|
{
|
|
/* success! */
|
|
updateCxt->updated = true;
|
|
updateCxt->crossPartUpdate = true;
|
|
|
|
/*
|
|
* If the partitioned table being updated is referenced in foreign
|
|
* keys, queue up trigger events to check that none of them were
|
|
* violated. No special treatment is needed in
|
|
* non-cross-partition update situations, because the leaf
|
|
* partition's AR update triggers will take care of that. During
|
|
* cross-partition updates implemented as delete on the source
|
|
* partition followed by insert on the destination partition,
|
|
* AR-UPDATE triggers of the root table (that is, the table
|
|
* mentioned in the query) must be fired.
|
|
*
|
|
* NULL insert_destrel means that the move failed to occur, that
|
|
* is, the update failed, so no need to anything in that case.
|
|
*/
|
|
if (insert_destrel &&
|
|
resultRelInfo->ri_TrigDesc &&
|
|
resultRelInfo->ri_TrigDesc->trig_update_after_row)
|
|
ExecCrossPartitionUpdateForeignKey(context,
|
|
resultRelInfo,
|
|
insert_destrel,
|
|
tupleid, slot,
|
|
inserted_tuple);
|
|
|
|
return TM_Ok;
|
|
}
|
|
|
|
/*
|
|
* No luck, a retry is needed. If running MERGE, we do not do so
|
|
* here; instead let it handle that on its own rules.
|
|
*/
|
|
if (context->relaction != NULL)
|
|
return result;
|
|
|
|
/*
|
|
* ExecCrossPartitionUpdate installed an updated version of the new
|
|
* tuple in the retry slot; start over.
|
|
*/
|
|
slot = retry_slot;
|
|
goto lreplace;
|
|
}
|
|
|
|
/*
|
|
* Check the constraints of the tuple. We've already checked the
|
|
* partition constraint above; however, we must still ensure the tuple
|
|
* passes all other constraints, so we will call ExecConstraints() and
|
|
* have it validate all remaining checks.
|
|
*/
|
|
if (resultRelationDesc->rd_att->constr)
|
|
ExecConstraints(resultRelInfo, slot, estate);
|
|
|
|
/*
|
|
* replace the heap tuple
|
|
*
|
|
* Note: if es_crosscheck_snapshot isn't InvalidSnapshot, we check that
|
|
* the row to be updated is visible to that snapshot, and throw a
|
|
* can't-serialize error if not. This is a special-case behavior needed
|
|
* for referential integrity updates in transaction-snapshot mode
|
|
* transactions.
|
|
*/
|
|
result = table_tuple_update(resultRelationDesc, tupleid, slot,
|
|
estate->es_output_cid,
|
|
estate->es_snapshot,
|
|
estate->es_crosscheck_snapshot,
|
|
true /* wait for commit */ ,
|
|
&context->tmfd, &updateCxt->lockmode,
|
|
&updateCxt->updateIndexes);
|
|
if (result == TM_Ok)
|
|
updateCxt->updated = true;
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* ExecUpdateEpilogue -- subroutine for ExecUpdate
|
|
*
|
|
* Closing steps of updating a tuple. Must be called if ExecUpdateAct
|
|
* returns indicating that the tuple was updated.
|
|
*/
|
|
static void
|
|
ExecUpdateEpilogue(ModifyTableContext *context, UpdateContext *updateCxt,
|
|
ResultRelInfo *resultRelInfo, ItemPointer tupleid,
|
|
HeapTuple oldtuple, TupleTableSlot *slot)
|
|
{
|
|
ModifyTableState *mtstate = context->mtstate;
|
|
List *recheckIndexes = NIL;
|
|
|
|
/* insert index entries for tuple if necessary */
|
|
if (resultRelInfo->ri_NumIndices > 0 && (updateCxt->updateIndexes != TU_None))
|
|
recheckIndexes = ExecInsertIndexTuples(resultRelInfo,
|
|
slot, context->estate,
|
|
true, false,
|
|
NULL, NIL,
|
|
(updateCxt->updateIndexes == TU_Summarizing));
|
|
|
|
/* AFTER ROW UPDATE Triggers */
|
|
ExecARUpdateTriggers(context->estate, resultRelInfo,
|
|
NULL, NULL,
|
|
tupleid, oldtuple, slot,
|
|
recheckIndexes,
|
|
mtstate->operation == CMD_INSERT ?
|
|
mtstate->mt_oc_transition_capture :
|
|
mtstate->mt_transition_capture,
|
|
false);
|
|
|
|
list_free(recheckIndexes);
|
|
|
|
/*
|
|
* Check any WITH CHECK OPTION constraints from parent views. We are
|
|
* required to do this after testing all constraints and uniqueness
|
|
* violations per the SQL spec, so we do it after actually updating the
|
|
* record in the heap and all indexes.
|
|
*
|
|
* ExecWithCheckOptions() will skip any WCOs which are not of the kind we
|
|
* are looking for at this point.
|
|
*/
|
|
if (resultRelInfo->ri_WithCheckOptions != NIL)
|
|
ExecWithCheckOptions(WCO_VIEW_CHECK, resultRelInfo,
|
|
slot, context->estate);
|
|
}
|
|
|
|
/*
|
|
* Queues up an update event using the target root partitioned table's
|
|
* trigger to check that a cross-partition update hasn't broken any foreign
|
|
* keys pointing into it.
|
|
*/
|
|
static void
|
|
ExecCrossPartitionUpdateForeignKey(ModifyTableContext *context,
|
|
ResultRelInfo *sourcePartInfo,
|
|
ResultRelInfo *destPartInfo,
|
|
ItemPointer tupleid,
|
|
TupleTableSlot *oldslot,
|
|
TupleTableSlot *newslot)
|
|
{
|
|
ListCell *lc;
|
|
ResultRelInfo *rootRelInfo;
|
|
List *ancestorRels;
|
|
|
|
rootRelInfo = sourcePartInfo->ri_RootResultRelInfo;
|
|
ancestorRels = ExecGetAncestorResultRels(context->estate, sourcePartInfo);
|
|
|
|
/*
|
|
* For any foreign keys that point directly into a non-root ancestors of
|
|
* the source partition, we can in theory fire an update event to enforce
|
|
* those constraints using their triggers, if we could tell that both the
|
|
* source and the destination partitions are under the same ancestor. But
|
|
* for now, we simply report an error that those cannot be enforced.
|
|
*/
|
|
foreach(lc, ancestorRels)
|
|
{
|
|
ResultRelInfo *rInfo = lfirst(lc);
|
|
TriggerDesc *trigdesc = rInfo->ri_TrigDesc;
|
|
bool has_noncloned_fkey = false;
|
|
|
|
/* Root ancestor's triggers will be processed. */
|
|
if (rInfo == rootRelInfo)
|
|
continue;
|
|
|
|
if (trigdesc && trigdesc->trig_update_after_row)
|
|
{
|
|
for (int i = 0; i < trigdesc->numtriggers; i++)
|
|
{
|
|
Trigger *trig = &trigdesc->triggers[i];
|
|
|
|
if (!trig->tgisclone &&
|
|
RI_FKey_trigger_type(trig->tgfoid) == RI_TRIGGER_PK)
|
|
{
|
|
has_noncloned_fkey = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (has_noncloned_fkey)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("cannot move tuple across partitions when a non-root ancestor of the source partition is directly referenced in a foreign key"),
|
|
errdetail("A foreign key points to ancestor \"%s\" but not the root ancestor \"%s\".",
|
|
RelationGetRelationName(rInfo->ri_RelationDesc),
|
|
RelationGetRelationName(rootRelInfo->ri_RelationDesc)),
|
|
errhint("Consider defining the foreign key on table \"%s\".",
|
|
RelationGetRelationName(rootRelInfo->ri_RelationDesc))));
|
|
}
|
|
|
|
/* Perform the root table's triggers. */
|
|
ExecARUpdateTriggers(context->estate,
|
|
rootRelInfo, sourcePartInfo, destPartInfo,
|
|
tupleid, NULL, newslot, NIL, NULL, true);
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecUpdate
|
|
*
|
|
* note: we can't run UPDATE queries with transactions
|
|
* off because UPDATEs are actually INSERTs and our
|
|
* scan will mistakenly loop forever, updating the tuple
|
|
* it just inserted.. This should be fixed but until it
|
|
* is, we don't want to get stuck in an infinite loop
|
|
* which corrupts your database..
|
|
*
|
|
* When updating a table, tupleid identifies the tuple to
|
|
* update and oldtuple is NULL. When updating a view, oldtuple
|
|
* is passed to the INSTEAD OF triggers and identifies what to
|
|
* update, and tupleid is invalid. When updating a foreign table,
|
|
* tupleid is invalid; the FDW has to figure out which row to
|
|
* update using data from the planSlot. oldtuple is passed to
|
|
* foreign table triggers; it is NULL when the foreign table has
|
|
* no relevant triggers.
|
|
*
|
|
* slot contains the new tuple value to be stored.
|
|
* planSlot is the output of the ModifyTable's subplan; we use it
|
|
* to access values from other input tables (for RETURNING),
|
|
* row-ID junk columns, etc.
|
|
*
|
|
* Returns RETURNING result if any, otherwise NULL.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static TupleTableSlot *
|
|
ExecUpdate(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
|
|
ItemPointer tupleid, HeapTuple oldtuple, TupleTableSlot *slot,
|
|
bool canSetTag)
|
|
{
|
|
EState *estate = context->estate;
|
|
Relation resultRelationDesc = resultRelInfo->ri_RelationDesc;
|
|
UpdateContext updateCxt = {0};
|
|
TM_Result result;
|
|
|
|
/*
|
|
* abort the operation if not running transactions
|
|
*/
|
|
if (IsBootstrapProcessingMode())
|
|
elog(ERROR, "cannot UPDATE during bootstrap");
|
|
|
|
/*
|
|
* Prepare for the update. This includes BEFORE ROW triggers, so we're
|
|
* done if it says we are.
|
|
*/
|
|
if (!ExecUpdatePrologue(context, resultRelInfo, tupleid, oldtuple, slot, NULL))
|
|
return NULL;
|
|
|
|
/* INSTEAD OF ROW UPDATE Triggers */
|
|
if (resultRelInfo->ri_TrigDesc &&
|
|
resultRelInfo->ri_TrigDesc->trig_update_instead_row)
|
|
{
|
|
if (!ExecIRUpdateTriggers(estate, resultRelInfo,
|
|
oldtuple, slot))
|
|
return NULL; /* "do nothing" */
|
|
}
|
|
else if (resultRelInfo->ri_FdwRoutine)
|
|
{
|
|
/* Fill in GENERATEd columns */
|
|
ExecUpdatePrepareSlot(resultRelInfo, slot, estate);
|
|
|
|
/*
|
|
* update in foreign table: let the FDW do it
|
|
*/
|
|
slot = resultRelInfo->ri_FdwRoutine->ExecForeignUpdate(estate,
|
|
resultRelInfo,
|
|
slot,
|
|
context->planSlot);
|
|
|
|
if (slot == NULL) /* "do nothing" */
|
|
return NULL;
|
|
|
|
/*
|
|
* AFTER ROW Triggers or RETURNING expressions might reference the
|
|
* tableoid column, so (re-)initialize tts_tableOid before evaluating
|
|
* them. (This covers the case where the FDW replaced the slot.)
|
|
*/
|
|
slot->tts_tableOid = RelationGetRelid(resultRelationDesc);
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* If we generate a new candidate tuple after EvalPlanQual testing, we
|
|
* must loop back here to try again. (We don't need to redo triggers,
|
|
* however. If there are any BEFORE triggers then trigger.c will have
|
|
* done table_tuple_lock to lock the correct tuple, so there's no need
|
|
* to do them again.)
|
|
*/
|
|
redo_act:
|
|
result = ExecUpdateAct(context, resultRelInfo, tupleid, oldtuple, slot,
|
|
canSetTag, &updateCxt);
|
|
|
|
/*
|
|
* If ExecUpdateAct reports that a cross-partition update was done,
|
|
* then the RETURNING tuple (if any) has been projected and there's
|
|
* nothing else for us to do.
|
|
*/
|
|
if (updateCxt.crossPartUpdate)
|
|
return context->cpUpdateReturningSlot;
|
|
|
|
switch (result)
|
|
{
|
|
case TM_SelfModified:
|
|
|
|
/*
|
|
* The target tuple was already updated or deleted by the
|
|
* current command, or by a later command in the current
|
|
* transaction. The former case is possible in a join UPDATE
|
|
* where multiple tuples join to the same target tuple. This
|
|
* is pretty questionable, but Postgres has always allowed it:
|
|
* we just execute the first update action and ignore
|
|
* additional update attempts.
|
|
*
|
|
* The latter case arises if the tuple is modified by a
|
|
* command in a BEFORE trigger, or perhaps by a command in a
|
|
* volatile function used in the query. In such situations we
|
|
* should not ignore the update, but it is equally unsafe to
|
|
* proceed. We don't want to discard the original UPDATE
|
|
* while keeping the triggered actions based on it; and we
|
|
* have no principled way to merge this update with the
|
|
* previous ones. So throwing an error is the only safe
|
|
* course.
|
|
*
|
|
* If a trigger actually intends this type of interaction, it
|
|
* can re-execute the UPDATE (assuming it can figure out how)
|
|
* and then return NULL to cancel the outer update.
|
|
*/
|
|
if (context->tmfd.cmax != estate->es_output_cid)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
|
|
errmsg("tuple to be updated was already modified by an operation triggered by the current command"),
|
|
errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
|
|
|
|
/* Else, already updated by self; nothing to do */
|
|
return NULL;
|
|
|
|
case TM_Ok:
|
|
break;
|
|
|
|
case TM_Updated:
|
|
{
|
|
TupleTableSlot *inputslot;
|
|
TupleTableSlot *epqslot;
|
|
TupleTableSlot *oldSlot;
|
|
|
|
if (IsolationUsesXactSnapshot())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("could not serialize access due to concurrent update")));
|
|
|
|
/*
|
|
* Already know that we're going to need to do EPQ, so
|
|
* fetch tuple directly into the right slot.
|
|
*/
|
|
inputslot = EvalPlanQualSlot(context->epqstate, resultRelationDesc,
|
|
resultRelInfo->ri_RangeTableIndex);
|
|
|
|
result = table_tuple_lock(resultRelationDesc, tupleid,
|
|
estate->es_snapshot,
|
|
inputslot, estate->es_output_cid,
|
|
updateCxt.lockmode, LockWaitBlock,
|
|
TUPLE_LOCK_FLAG_FIND_LAST_VERSION,
|
|
&context->tmfd);
|
|
|
|
switch (result)
|
|
{
|
|
case TM_Ok:
|
|
Assert(context->tmfd.traversed);
|
|
|
|
epqslot = EvalPlanQual(context->epqstate,
|
|
resultRelationDesc,
|
|
resultRelInfo->ri_RangeTableIndex,
|
|
inputslot);
|
|
if (TupIsNull(epqslot))
|
|
/* Tuple not passing quals anymore, exiting... */
|
|
return NULL;
|
|
|
|
/* Make sure ri_oldTupleSlot is initialized. */
|
|
if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
|
|
ExecInitUpdateProjection(context->mtstate,
|
|
resultRelInfo);
|
|
|
|
/* Fetch the most recent version of old tuple. */
|
|
oldSlot = resultRelInfo->ri_oldTupleSlot;
|
|
if (!table_tuple_fetch_row_version(resultRelationDesc,
|
|
tupleid,
|
|
SnapshotAny,
|
|
oldSlot))
|
|
elog(ERROR, "failed to fetch tuple being updated");
|
|
slot = ExecGetUpdateNewTuple(resultRelInfo,
|
|
epqslot, oldSlot);
|
|
goto redo_act;
|
|
|
|
case TM_Deleted:
|
|
/* tuple already deleted; nothing to do */
|
|
return NULL;
|
|
|
|
case TM_SelfModified:
|
|
|
|
/*
|
|
* This can be reached when following an update
|
|
* chain from a tuple updated by another session,
|
|
* reaching a tuple that was already updated in
|
|
* this transaction. If previously modified by
|
|
* this command, ignore the redundant update,
|
|
* otherwise error out.
|
|
*
|
|
* See also TM_SelfModified response to
|
|
* table_tuple_update() above.
|
|
*/
|
|
if (context->tmfd.cmax != estate->es_output_cid)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
|
|
errmsg("tuple to be updated was already modified by an operation triggered by the current command"),
|
|
errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
|
|
return NULL;
|
|
|
|
default:
|
|
/* see table_tuple_lock call in ExecDelete() */
|
|
elog(ERROR, "unexpected table_tuple_lock status: %u",
|
|
result);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
break;
|
|
|
|
case TM_Deleted:
|
|
if (IsolationUsesXactSnapshot())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("could not serialize access due to concurrent delete")));
|
|
/* tuple already deleted; nothing to do */
|
|
return NULL;
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized table_tuple_update status: %u",
|
|
result);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
if (canSetTag)
|
|
(estate->es_processed)++;
|
|
|
|
ExecUpdateEpilogue(context, &updateCxt, resultRelInfo, tupleid, oldtuple,
|
|
slot);
|
|
|
|
/* Process RETURNING if present */
|
|
if (resultRelInfo->ri_projectReturning)
|
|
return ExecProcessReturning(resultRelInfo, slot, context->planSlot);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* ExecOnConflictUpdate --- execute UPDATE of INSERT ON CONFLICT DO UPDATE
|
|
*
|
|
* Try to lock tuple for update as part of speculative insertion. If
|
|
* a qual originating from ON CONFLICT DO UPDATE is satisfied, update
|
|
* (but still lock row, even though it may not satisfy estate's
|
|
* snapshot).
|
|
*
|
|
* Returns true if we're done (with or without an update), or false if
|
|
* the caller must retry the INSERT from scratch.
|
|
*/
|
|
static bool
|
|
ExecOnConflictUpdate(ModifyTableContext *context,
|
|
ResultRelInfo *resultRelInfo,
|
|
ItemPointer conflictTid,
|
|
TupleTableSlot *excludedSlot,
|
|
bool canSetTag,
|
|
TupleTableSlot **returning)
|
|
{
|
|
ModifyTableState *mtstate = context->mtstate;
|
|
ExprContext *econtext = mtstate->ps.ps_ExprContext;
|
|
Relation relation = resultRelInfo->ri_RelationDesc;
|
|
ExprState *onConflictSetWhere = resultRelInfo->ri_onConflict->oc_WhereClause;
|
|
TupleTableSlot *existing = resultRelInfo->ri_onConflict->oc_Existing;
|
|
TM_FailureData tmfd;
|
|
LockTupleMode lockmode;
|
|
TM_Result test;
|
|
Datum xminDatum;
|
|
TransactionId xmin;
|
|
bool isnull;
|
|
|
|
/* Determine lock mode to use */
|
|
lockmode = ExecUpdateLockMode(context->estate, resultRelInfo);
|
|
|
|
/*
|
|
* Lock tuple for update. Don't follow updates when tuple cannot be
|
|
* locked without doing so. A row locking conflict here means our
|
|
* previous conclusion that the tuple is conclusively committed is not
|
|
* true anymore.
|
|
*/
|
|
test = table_tuple_lock(relation, conflictTid,
|
|
context->estate->es_snapshot,
|
|
existing, context->estate->es_output_cid,
|
|
lockmode, LockWaitBlock, 0,
|
|
&tmfd);
|
|
switch (test)
|
|
{
|
|
case TM_Ok:
|
|
/* success! */
|
|
break;
|
|
|
|
case TM_Invisible:
|
|
|
|
/*
|
|
* This can occur when a just inserted tuple is updated again in
|
|
* the same command. E.g. because multiple rows with the same
|
|
* conflicting key values are inserted.
|
|
*
|
|
* This is somewhat similar to the ExecUpdate() TM_SelfModified
|
|
* case. We do not want to proceed because it would lead to the
|
|
* same row being updated a second time in some unspecified order,
|
|
* and in contrast to plain UPDATEs there's no historical behavior
|
|
* to break.
|
|
*
|
|
* It is the user's responsibility to prevent this situation from
|
|
* occurring. These problems are why the SQL standard similarly
|
|
* specifies that for SQL MERGE, an exception must be raised in
|
|
* the event of an attempt to update the same row twice.
|
|
*/
|
|
xminDatum = slot_getsysattr(existing,
|
|
MinTransactionIdAttributeNumber,
|
|
&isnull);
|
|
Assert(!isnull);
|
|
xmin = DatumGetTransactionId(xminDatum);
|
|
|
|
if (TransactionIdIsCurrentTransactionId(xmin))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_CARDINALITY_VIOLATION),
|
|
/* translator: %s is a SQL command name */
|
|
errmsg("%s command cannot affect row a second time",
|
|
"ON CONFLICT DO UPDATE"),
|
|
errhint("Ensure that no rows proposed for insertion within the same command have duplicate constrained values.")));
|
|
|
|
/* This shouldn't happen */
|
|
elog(ERROR, "attempted to lock invisible tuple");
|
|
break;
|
|
|
|
case TM_SelfModified:
|
|
|
|
/*
|
|
* This state should never be reached. As a dirty snapshot is used
|
|
* to find conflicting tuples, speculative insertion wouldn't have
|
|
* seen this row to conflict with.
|
|
*/
|
|
elog(ERROR, "unexpected self-updated tuple");
|
|
break;
|
|
|
|
case TM_Updated:
|
|
if (IsolationUsesXactSnapshot())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("could not serialize access due to concurrent update")));
|
|
|
|
/*
|
|
* As long as we don't support an UPDATE of INSERT ON CONFLICT for
|
|
* a partitioned table we shouldn't reach to a case where tuple to
|
|
* be lock is moved to another partition due to concurrent update
|
|
* of the partition key.
|
|
*/
|
|
Assert(!ItemPointerIndicatesMovedPartitions(&tmfd.ctid));
|
|
|
|
/*
|
|
* Tell caller to try again from the very start.
|
|
*
|
|
* It does not make sense to use the usual EvalPlanQual() style
|
|
* loop here, as the new version of the row might not conflict
|
|
* anymore, or the conflicting tuple has actually been deleted.
|
|
*/
|
|
ExecClearTuple(existing);
|
|
return false;
|
|
|
|
case TM_Deleted:
|
|
if (IsolationUsesXactSnapshot())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("could not serialize access due to concurrent delete")));
|
|
|
|
/* see TM_Updated case */
|
|
Assert(!ItemPointerIndicatesMovedPartitions(&tmfd.ctid));
|
|
ExecClearTuple(existing);
|
|
return false;
|
|
|
|
default:
|
|
elog(ERROR, "unrecognized table_tuple_lock status: %u", test);
|
|
}
|
|
|
|
/* Success, the tuple is locked. */
|
|
|
|
/*
|
|
* Verify that the tuple is visible to our MVCC snapshot if the current
|
|
* isolation level mandates that.
|
|
*
|
|
* It's not sufficient to rely on the check within ExecUpdate() as e.g.
|
|
* CONFLICT ... WHERE clause may prevent us from reaching that.
|
|
*
|
|
* This means we only ever continue when a new command in the current
|
|
* transaction could see the row, even though in READ COMMITTED mode the
|
|
* tuple will not be visible according to the current statement's
|
|
* snapshot. This is in line with the way UPDATE deals with newer tuple
|
|
* versions.
|
|
*/
|
|
ExecCheckTupleVisible(context->estate, relation, existing);
|
|
|
|
/*
|
|
* Make tuple and any needed join variables available to ExecQual and
|
|
* ExecProject. The EXCLUDED tuple is installed in ecxt_innertuple, while
|
|
* the target's existing tuple is installed in the scantuple. EXCLUDED
|
|
* has been made to reference INNER_VAR in setrefs.c, but there is no
|
|
* other redirection.
|
|
*/
|
|
econtext->ecxt_scantuple = existing;
|
|
econtext->ecxt_innertuple = excludedSlot;
|
|
econtext->ecxt_outertuple = NULL;
|
|
|
|
if (!ExecQual(onConflictSetWhere, econtext))
|
|
{
|
|
ExecClearTuple(existing); /* see return below */
|
|
InstrCountFiltered1(&mtstate->ps, 1);
|
|
return true; /* done with the tuple */
|
|
}
|
|
|
|
if (resultRelInfo->ri_WithCheckOptions != NIL)
|
|
{
|
|
/*
|
|
* Check target's existing tuple against UPDATE-applicable USING
|
|
* security barrier quals (if any), enforced here as RLS checks/WCOs.
|
|
*
|
|
* The rewriter creates UPDATE RLS checks/WCOs for UPDATE security
|
|
* quals, and stores them as WCOs of "kind" WCO_RLS_CONFLICT_CHECK,
|
|
* but that's almost the extent of its special handling for ON
|
|
* CONFLICT DO UPDATE.
|
|
*
|
|
* The rewriter will also have associated UPDATE applicable straight
|
|
* RLS checks/WCOs for the benefit of the ExecUpdate() call that
|
|
* follows. INSERTs and UPDATEs naturally have mutually exclusive WCO
|
|
* kinds, so there is no danger of spurious over-enforcement in the
|
|
* INSERT or UPDATE path.
|
|
*/
|
|
ExecWithCheckOptions(WCO_RLS_CONFLICT_CHECK, resultRelInfo,
|
|
existing,
|
|
mtstate->ps.state);
|
|
}
|
|
|
|
/* Project the new tuple version */
|
|
ExecProject(resultRelInfo->ri_onConflict->oc_ProjInfo);
|
|
|
|
/*
|
|
* Note that it is possible that the target tuple has been modified in
|
|
* this session, after the above table_tuple_lock. We choose to not error
|
|
* out in that case, in line with ExecUpdate's treatment of similar cases.
|
|
* This can happen if an UPDATE is triggered from within ExecQual(),
|
|
* ExecWithCheckOptions() or ExecProject() above, e.g. by selecting from a
|
|
* wCTE in the ON CONFLICT's SET.
|
|
*/
|
|
|
|
/* Execute UPDATE with projection */
|
|
*returning = ExecUpdate(context, resultRelInfo,
|
|
conflictTid, NULL,
|
|
resultRelInfo->ri_onConflict->oc_ProjSlot,
|
|
canSetTag);
|
|
|
|
/*
|
|
* Clear out existing tuple, as there might not be another conflict among
|
|
* the next input rows. Don't want to hold resources till the end of the
|
|
* query.
|
|
*/
|
|
ExecClearTuple(existing);
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Perform MERGE.
|
|
*/
|
|
static TupleTableSlot *
|
|
ExecMerge(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
|
|
ItemPointer tupleid, bool canSetTag)
|
|
{
|
|
bool matched;
|
|
|
|
/*-----
|
|
* If we are dealing with a WHEN MATCHED case (tupleid is valid), we
|
|
* execute the first action for which the additional WHEN MATCHED AND
|
|
* quals pass. If an action without quals is found, that action is
|
|
* executed.
|
|
*
|
|
* Similarly, if we are dealing with WHEN NOT MATCHED case, we look at
|
|
* the given WHEN NOT MATCHED actions in sequence until one passes.
|
|
*
|
|
* Things get interesting in case of concurrent update/delete of the
|
|
* target tuple. Such concurrent update/delete is detected while we are
|
|
* executing a WHEN MATCHED action.
|
|
*
|
|
* A concurrent update can:
|
|
*
|
|
* 1. modify the target tuple so that it no longer satisfies the
|
|
* additional quals attached to the current WHEN MATCHED action
|
|
*
|
|
* In this case, we are still dealing with a WHEN MATCHED case.
|
|
* We recheck the list of WHEN MATCHED actions from the start and
|
|
* choose the first one that satisfies the new target tuple.
|
|
*
|
|
* 2. modify the target tuple so that the join quals no longer pass and
|
|
* hence the source tuple no longer has a match.
|
|
*
|
|
* In this case, the source tuple no longer matches the target tuple,
|
|
* so we now instead find a qualifying WHEN NOT MATCHED action to
|
|
* execute.
|
|
*
|
|
* XXX Hmmm, what if the updated tuple would now match one that was
|
|
* considered NOT MATCHED so far?
|
|
*
|
|
* A concurrent delete changes a WHEN MATCHED case to WHEN NOT MATCHED.
|
|
*
|
|
* ExecMergeMatched takes care of following the update chain and
|
|
* re-finding the qualifying WHEN MATCHED action, as long as the updated
|
|
* target tuple still satisfies the join quals, i.e., it remains a WHEN
|
|
* MATCHED case. If the tuple gets deleted or the join quals fail, it
|
|
* returns and we try ExecMergeNotMatched. Given that ExecMergeMatched
|
|
* always make progress by following the update chain and we never switch
|
|
* from ExecMergeNotMatched to ExecMergeMatched, there is no risk of a
|
|
* livelock.
|
|
*/
|
|
matched = tupleid != NULL;
|
|
if (matched)
|
|
matched = ExecMergeMatched(context, resultRelInfo, tupleid, canSetTag);
|
|
|
|
/*
|
|
* Either we were dealing with a NOT MATCHED tuple or ExecMergeMatched()
|
|
* returned "false", indicating the previously MATCHED tuple no longer
|
|
* matches.
|
|
*/
|
|
if (!matched)
|
|
ExecMergeNotMatched(context, resultRelInfo, canSetTag);
|
|
|
|
/* No RETURNING support yet */
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Check and execute the first qualifying MATCHED action. The current target
|
|
* tuple is identified by tupleid.
|
|
*
|
|
* We start from the first WHEN MATCHED action and check if the WHEN quals
|
|
* pass, if any. If the WHEN quals for the first action do not pass, we
|
|
* check the second, then the third and so on. If we reach to the end, no
|
|
* action is taken and we return true, indicating that no further action is
|
|
* required for this tuple.
|
|
*
|
|
* If we do find a qualifying action, then we attempt to execute the action.
|
|
*
|
|
* If the tuple is concurrently updated, EvalPlanQual is run with the updated
|
|
* tuple to recheck the join quals. Note that the additional quals associated
|
|
* with individual actions are evaluated by this routine via ExecQual, while
|
|
* EvalPlanQual checks for the join quals. If EvalPlanQual tells us that the
|
|
* updated tuple still passes the join quals, then we restart from the first
|
|
* action to look for a qualifying action. Otherwise, we return false --
|
|
* meaning that a NOT MATCHED action must now be executed for the current
|
|
* source tuple.
|
|
*/
|
|
static bool
|
|
ExecMergeMatched(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
|
|
ItemPointer tupleid, bool canSetTag)
|
|
{
|
|
ModifyTableState *mtstate = context->mtstate;
|
|
TupleTableSlot *newslot;
|
|
EState *estate = context->estate;
|
|
ExprContext *econtext = mtstate->ps.ps_ExprContext;
|
|
bool isNull;
|
|
EPQState *epqstate = &mtstate->mt_epqstate;
|
|
ListCell *l;
|
|
|
|
/*
|
|
* If there are no WHEN MATCHED actions, we are done.
|
|
*/
|
|
if (resultRelInfo->ri_matchedMergeAction == NIL)
|
|
return true;
|
|
|
|
/*
|
|
* Make tuple and any needed join variables available to ExecQual and
|
|
* ExecProject. The target's existing tuple is installed in the scantuple.
|
|
* Again, this target relation's slot is required only in the case of a
|
|
* MATCHED tuple and UPDATE/DELETE actions.
|
|
*/
|
|
econtext->ecxt_scantuple = resultRelInfo->ri_oldTupleSlot;
|
|
econtext->ecxt_innertuple = context->planSlot;
|
|
econtext->ecxt_outertuple = NULL;
|
|
|
|
lmerge_matched:
|
|
|
|
/*
|
|
* This routine is only invoked for matched rows, and we must have found
|
|
* the tupleid of the target row in that case; fetch that tuple.
|
|
*
|
|
* We use SnapshotAny for this because we might get called again after
|
|
* EvalPlanQual returns us a new tuple, which may not be visible to our
|
|
* MVCC snapshot.
|
|
*/
|
|
|
|
if (!table_tuple_fetch_row_version(resultRelInfo->ri_RelationDesc,
|
|
tupleid,
|
|
SnapshotAny,
|
|
resultRelInfo->ri_oldTupleSlot))
|
|
elog(ERROR, "failed to fetch the target tuple");
|
|
|
|
foreach(l, resultRelInfo->ri_matchedMergeAction)
|
|
{
|
|
MergeActionState *relaction = (MergeActionState *) lfirst(l);
|
|
CmdType commandType = relaction->mas_action->commandType;
|
|
TM_Result result;
|
|
UpdateContext updateCxt = {0};
|
|
|
|
/*
|
|
* Test condition, if any.
|
|
*
|
|
* In the absence of any condition, we perform the action
|
|
* unconditionally (no need to check separately since ExecQual() will
|
|
* return true if there are no conditions to evaluate).
|
|
*/
|
|
if (!ExecQual(relaction->mas_whenqual, econtext))
|
|
continue;
|
|
|
|
/*
|
|
* Check if the existing target tuple meets the USING checks of
|
|
* UPDATE/DELETE RLS policies. If those checks fail, we throw an
|
|
* error.
|
|
*
|
|
* The WITH CHECK quals for UPDATE RLS policies are applied in
|
|
* ExecUpdateAct() and hence we need not do anything special to handle
|
|
* them.
|
|
*
|
|
* NOTE: We must do this after WHEN quals are evaluated, so that we
|
|
* check policies only when they matter.
|
|
*/
|
|
if (resultRelInfo->ri_WithCheckOptions && commandType != CMD_NOTHING)
|
|
{
|
|
ExecWithCheckOptions(commandType == CMD_UPDATE ?
|
|
WCO_RLS_MERGE_UPDATE_CHECK : WCO_RLS_MERGE_DELETE_CHECK,
|
|
resultRelInfo,
|
|
resultRelInfo->ri_oldTupleSlot,
|
|
context->mtstate->ps.state);
|
|
}
|
|
|
|
/* Perform stated action */
|
|
switch (commandType)
|
|
{
|
|
case CMD_UPDATE:
|
|
|
|
/*
|
|
* Project the output tuple, and use that to update the table.
|
|
* We don't need to filter out junk attributes, because the
|
|
* UPDATE action's targetlist doesn't have any.
|
|
*/
|
|
newslot = ExecProject(relaction->mas_proj);
|
|
|
|
context->relaction = relaction;
|
|
if (!ExecUpdatePrologue(context, resultRelInfo,
|
|
tupleid, NULL, newslot, &result))
|
|
{
|
|
if (result == TM_Ok)
|
|
return true; /* "do nothing" */
|
|
break; /* concurrent update/delete */
|
|
}
|
|
result = ExecUpdateAct(context, resultRelInfo, tupleid, NULL,
|
|
newslot, canSetTag, &updateCxt);
|
|
|
|
/*
|
|
* As in ExecUpdate(), if ExecUpdateAct() reports that a
|
|
* cross-partition update was done, then there's nothing else
|
|
* for us to do --- the UPDATE has been turned into a DELETE
|
|
* and an INSERT, and we must not perform any of the usual
|
|
* post-update tasks.
|
|
*/
|
|
if (updateCxt.crossPartUpdate)
|
|
{
|
|
mtstate->mt_merge_updated += 1;
|
|
return true;
|
|
}
|
|
|
|
if (result == TM_Ok && updateCxt.updated)
|
|
{
|
|
ExecUpdateEpilogue(context, &updateCxt, resultRelInfo,
|
|
tupleid, NULL, newslot);
|
|
mtstate->mt_merge_updated += 1;
|
|
}
|
|
break;
|
|
|
|
case CMD_DELETE:
|
|
context->relaction = relaction;
|
|
if (!ExecDeletePrologue(context, resultRelInfo, tupleid,
|
|
NULL, NULL, &result))
|
|
{
|
|
if (result == TM_Ok)
|
|
return true; /* "do nothing" */
|
|
break; /* concurrent update/delete */
|
|
}
|
|
result = ExecDeleteAct(context, resultRelInfo, tupleid, false);
|
|
if (result == TM_Ok)
|
|
{
|
|
ExecDeleteEpilogue(context, resultRelInfo, tupleid, NULL,
|
|
false);
|
|
mtstate->mt_merge_deleted += 1;
|
|
}
|
|
break;
|
|
|
|
case CMD_NOTHING:
|
|
/* Doing nothing is always OK */
|
|
result = TM_Ok;
|
|
break;
|
|
|
|
default:
|
|
elog(ERROR, "unknown action in MERGE WHEN MATCHED clause");
|
|
}
|
|
|
|
switch (result)
|
|
{
|
|
case TM_Ok:
|
|
/* all good; perform final actions */
|
|
if (canSetTag && commandType != CMD_NOTHING)
|
|
(estate->es_processed)++;
|
|
|
|
break;
|
|
|
|
case TM_SelfModified:
|
|
|
|
/*
|
|
* The SQL standard disallows this for MERGE.
|
|
*/
|
|
if (TransactionIdIsCurrentTransactionId(context->tmfd.xmax))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_CARDINALITY_VIOLATION),
|
|
/* translator: %s is a SQL command name */
|
|
errmsg("%s command cannot affect row a second time",
|
|
"MERGE"),
|
|
errhint("Ensure that not more than one source row matches any one target row.")));
|
|
/* This shouldn't happen */
|
|
elog(ERROR, "attempted to update or delete invisible tuple");
|
|
break;
|
|
|
|
case TM_Deleted:
|
|
if (IsolationUsesXactSnapshot())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("could not serialize access due to concurrent delete")));
|
|
|
|
/*
|
|
* If the tuple was already deleted, return to let caller
|
|
* handle it under NOT MATCHED clauses.
|
|
*/
|
|
return false;
|
|
|
|
case TM_Updated:
|
|
{
|
|
Relation resultRelationDesc;
|
|
TupleTableSlot *epqslot,
|
|
*inputslot;
|
|
LockTupleMode lockmode;
|
|
|
|
/*
|
|
* The target tuple was concurrently updated by some other
|
|
* transaction. Run EvalPlanQual() with the new version of
|
|
* the tuple. If it does not return a tuple, then we
|
|
* switch to the NOT MATCHED list of actions. If it does
|
|
* return a tuple and the join qual is still satisfied,
|
|
* then we just need to recheck the MATCHED actions,
|
|
* starting from the top, and execute the first qualifying
|
|
* action.
|
|
*/
|
|
resultRelationDesc = resultRelInfo->ri_RelationDesc;
|
|
lockmode = ExecUpdateLockMode(estate, resultRelInfo);
|
|
|
|
inputslot = EvalPlanQualSlot(epqstate, resultRelationDesc,
|
|
resultRelInfo->ri_RangeTableIndex);
|
|
|
|
result = table_tuple_lock(resultRelationDesc, tupleid,
|
|
estate->es_snapshot,
|
|
inputslot, estate->es_output_cid,
|
|
lockmode, LockWaitBlock,
|
|
TUPLE_LOCK_FLAG_FIND_LAST_VERSION,
|
|
&context->tmfd);
|
|
switch (result)
|
|
{
|
|
case TM_Ok:
|
|
epqslot = EvalPlanQual(epqstate,
|
|
resultRelationDesc,
|
|
resultRelInfo->ri_RangeTableIndex,
|
|
inputslot);
|
|
|
|
/*
|
|
* If we got no tuple, or the tuple we get has a
|
|
* NULL ctid, go back to caller: this one is not a
|
|
* MATCHED tuple anymore, so they can retry with
|
|
* NOT MATCHED actions.
|
|
*/
|
|
if (TupIsNull(epqslot))
|
|
return false;
|
|
|
|
(void) ExecGetJunkAttribute(epqslot,
|
|
resultRelInfo->ri_RowIdAttNo,
|
|
&isNull);
|
|
if (isNull)
|
|
return false;
|
|
|
|
/*
|
|
* When a tuple was updated and migrated to
|
|
* another partition concurrently, the current
|
|
* MERGE implementation can't follow. There's
|
|
* probably a better way to handle this case, but
|
|
* it'd require recognizing the relation to which
|
|
* the tuple moved, and setting our current
|
|
* resultRelInfo to that.
|
|
*/
|
|
if (ItemPointerIndicatesMovedPartitions(&context->tmfd.ctid))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
|
|
errmsg("tuple to be deleted was already moved to another partition due to concurrent update")));
|
|
|
|
/*
|
|
* A non-NULL ctid means that we are still dealing
|
|
* with MATCHED case. Restart the loop so that we
|
|
* apply all the MATCHED rules again, to ensure
|
|
* that the first qualifying WHEN MATCHED action
|
|
* is executed.
|
|
*
|
|
* Update tupleid to that of the new tuple, for
|
|
* the refetch we do at the top.
|
|
*/
|
|
ItemPointerCopy(&context->tmfd.ctid, tupleid);
|
|
goto lmerge_matched;
|
|
|
|
case TM_Deleted:
|
|
|
|
/*
|
|
* tuple already deleted; tell caller to run NOT
|
|
* MATCHED actions
|
|
*/
|
|
return false;
|
|
|
|
case TM_SelfModified:
|
|
|
|
/*
|
|
* This can be reached when following an update
|
|
* chain from a tuple updated by another session,
|
|
* reaching a tuple that was already updated in
|
|
* this transaction. If previously modified by
|
|
* this command, ignore the redundant update,
|
|
* otherwise error out.
|
|
*
|
|
* See also response to TM_SelfModified in
|
|
* ExecUpdate().
|
|
*/
|
|
if (context->tmfd.cmax != estate->es_output_cid)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_TRIGGERED_DATA_CHANGE_VIOLATION),
|
|
errmsg("tuple to be updated or deleted was already modified by an operation triggered by the current command"),
|
|
errhint("Consider using an AFTER trigger instead of a BEFORE trigger to propagate changes to other rows.")));
|
|
return false;
|
|
|
|
default:
|
|
/* see table_tuple_lock call in ExecDelete() */
|
|
elog(ERROR, "unexpected table_tuple_lock status: %u",
|
|
result);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
case TM_Invisible:
|
|
case TM_WouldBlock:
|
|
case TM_BeingModified:
|
|
/* these should not occur */
|
|
elog(ERROR, "unexpected tuple operation result: %d", result);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* We've activated one of the WHEN clauses, so we don't search
|
|
* further. This is required behaviour, not an optimization.
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Successfully executed an action or no qualifying action was found.
|
|
*/
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Execute the first qualifying NOT MATCHED action.
|
|
*/
|
|
static void
|
|
ExecMergeNotMatched(ModifyTableContext *context, ResultRelInfo *resultRelInfo,
|
|
bool canSetTag)
|
|
{
|
|
ModifyTableState *mtstate = context->mtstate;
|
|
ExprContext *econtext = mtstate->ps.ps_ExprContext;
|
|
List *actionStates = NIL;
|
|
ListCell *l;
|
|
|
|
/*
|
|
* For INSERT actions, the root relation's merge action is OK since the
|
|
* INSERT's targetlist and the WHEN conditions can only refer to the
|
|
* source relation and hence it does not matter which result relation we
|
|
* work with.
|
|
*
|
|
* XXX does this mean that we can avoid creating copies of actionStates on
|
|
* partitioned tables, for not-matched actions?
|
|
*/
|
|
actionStates = resultRelInfo->ri_notMatchedMergeAction;
|
|
|
|
/*
|
|
* Make source tuple available to ExecQual and ExecProject. We don't need
|
|
* the target tuple, since the WHEN quals and targetlist can't refer to
|
|
* the target columns.
|
|
*/
|
|
econtext->ecxt_scantuple = NULL;
|
|
econtext->ecxt_innertuple = context->planSlot;
|
|
econtext->ecxt_outertuple = NULL;
|
|
|
|
foreach(l, actionStates)
|
|
{
|
|
MergeActionState *action = (MergeActionState *) lfirst(l);
|
|
CmdType commandType = action->mas_action->commandType;
|
|
TupleTableSlot *newslot;
|
|
|
|
/*
|
|
* Test condition, if any.
|
|
*
|
|
* In the absence of any condition, we perform the action
|
|
* unconditionally (no need to check separately since ExecQual() will
|
|
* return true if there are no conditions to evaluate).
|
|
*/
|
|
if (!ExecQual(action->mas_whenqual, econtext))
|
|
continue;
|
|
|
|
/* Perform stated action */
|
|
switch (commandType)
|
|
{
|
|
case CMD_INSERT:
|
|
|
|
/*
|
|
* Project the tuple. In case of a partitioned table, the
|
|
* projection was already built to use the root's descriptor,
|
|
* so we don't need to map the tuple here.
|
|
*/
|
|
newslot = ExecProject(action->mas_proj);
|
|
context->relaction = action;
|
|
|
|
(void) ExecInsert(context, mtstate->rootResultRelInfo, newslot,
|
|
canSetTag, NULL, NULL);
|
|
mtstate->mt_merge_inserted += 1;
|
|
break;
|
|
case CMD_NOTHING:
|
|
/* Do nothing */
|
|
break;
|
|
default:
|
|
elog(ERROR, "unknown action in MERGE WHEN NOT MATCHED clause");
|
|
}
|
|
|
|
/*
|
|
* We've activated one of the WHEN clauses, so we don't search
|
|
* further. This is required behaviour, not an optimization.
|
|
*/
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Initialize state for execution of MERGE.
|
|
*/
|
|
void
|
|
ExecInitMerge(ModifyTableState *mtstate, EState *estate)
|
|
{
|
|
ModifyTable *node = (ModifyTable *) mtstate->ps.plan;
|
|
ResultRelInfo *rootRelInfo = mtstate->rootResultRelInfo;
|
|
ResultRelInfo *resultRelInfo;
|
|
ExprContext *econtext;
|
|
ListCell *lc;
|
|
int i;
|
|
|
|
if (node->mergeActionLists == NIL)
|
|
return;
|
|
|
|
mtstate->mt_merge_subcommands = 0;
|
|
|
|
if (mtstate->ps.ps_ExprContext == NULL)
|
|
ExecAssignExprContext(estate, &mtstate->ps);
|
|
econtext = mtstate->ps.ps_ExprContext;
|
|
|
|
/*
|
|
* Create a MergeActionState for each action on the mergeActionList and
|
|
* add it to either a list of matched actions or not-matched actions.
|
|
*
|
|
* Similar logic appears in ExecInitPartitionInfo(), so if changing
|
|
* anything here, do so there too.
|
|
*/
|
|
i = 0;
|
|
foreach(lc, node->mergeActionLists)
|
|
{
|
|
List *mergeActionList = lfirst(lc);
|
|
TupleDesc relationDesc;
|
|
ListCell *l;
|
|
|
|
resultRelInfo = mtstate->resultRelInfo + i;
|
|
i++;
|
|
relationDesc = RelationGetDescr(resultRelInfo->ri_RelationDesc);
|
|
|
|
/* initialize slots for MERGE fetches from this rel */
|
|
if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
|
|
ExecInitMergeTupleSlots(mtstate, resultRelInfo);
|
|
|
|
foreach(l, mergeActionList)
|
|
{
|
|
MergeAction *action = (MergeAction *) lfirst(l);
|
|
MergeActionState *action_state;
|
|
TupleTableSlot *tgtslot;
|
|
TupleDesc tgtdesc;
|
|
List **list;
|
|
|
|
/*
|
|
* Build action merge state for this rel. (For partitions,
|
|
* equivalent code exists in ExecInitPartitionInfo.)
|
|
*/
|
|
action_state = makeNode(MergeActionState);
|
|
action_state->mas_action = action;
|
|
action_state->mas_whenqual = ExecInitQual((List *) action->qual,
|
|
&mtstate->ps);
|
|
|
|
/*
|
|
* We create two lists - one for WHEN MATCHED actions and one for
|
|
* WHEN NOT MATCHED actions - and stick the MergeActionState into
|
|
* the appropriate list.
|
|
*/
|
|
if (action_state->mas_action->matched)
|
|
list = &resultRelInfo->ri_matchedMergeAction;
|
|
else
|
|
list = &resultRelInfo->ri_notMatchedMergeAction;
|
|
*list = lappend(*list, action_state);
|
|
|
|
switch (action->commandType)
|
|
{
|
|
case CMD_INSERT:
|
|
ExecCheckPlanOutput(rootRelInfo->ri_RelationDesc,
|
|
action->targetList);
|
|
|
|
/*
|
|
* If the MERGE targets a partitioned table, any INSERT
|
|
* actions must be routed through it, not the child
|
|
* relations. Initialize the routing struct and the root
|
|
* table's "new" tuple slot for that, if not already done.
|
|
* The projection we prepare, for all relations, uses the
|
|
* root relation descriptor, and targets the plan's root
|
|
* slot. (This is consistent with the fact that we
|
|
* checked the plan output to match the root relation,
|
|
* above.)
|
|
*/
|
|
if (rootRelInfo->ri_RelationDesc->rd_rel->relkind ==
|
|
RELKIND_PARTITIONED_TABLE)
|
|
{
|
|
if (mtstate->mt_partition_tuple_routing == NULL)
|
|
{
|
|
/*
|
|
* Initialize planstate for routing if not already
|
|
* done.
|
|
*
|
|
* Note that the slot is managed as a standalone
|
|
* slot belonging to ModifyTableState, so we pass
|
|
* NULL for the 2nd argument.
|
|
*/
|
|
mtstate->mt_root_tuple_slot =
|
|
table_slot_create(rootRelInfo->ri_RelationDesc,
|
|
NULL);
|
|
mtstate->mt_partition_tuple_routing =
|
|
ExecSetupPartitionTupleRouting(estate,
|
|
rootRelInfo->ri_RelationDesc);
|
|
}
|
|
tgtslot = mtstate->mt_root_tuple_slot;
|
|
tgtdesc = RelationGetDescr(rootRelInfo->ri_RelationDesc);
|
|
}
|
|
else
|
|
{
|
|
/* not partitioned? use the stock relation and slot */
|
|
tgtslot = resultRelInfo->ri_newTupleSlot;
|
|
tgtdesc = RelationGetDescr(resultRelInfo->ri_RelationDesc);
|
|
}
|
|
|
|
action_state->mas_proj =
|
|
ExecBuildProjectionInfo(action->targetList, econtext,
|
|
tgtslot,
|
|
&mtstate->ps,
|
|
tgtdesc);
|
|
|
|
mtstate->mt_merge_subcommands |= MERGE_INSERT;
|
|
break;
|
|
case CMD_UPDATE:
|
|
action_state->mas_proj =
|
|
ExecBuildUpdateProjection(action->targetList,
|
|
true,
|
|
action->updateColnos,
|
|
relationDesc,
|
|
econtext,
|
|
resultRelInfo->ri_newTupleSlot,
|
|
&mtstate->ps);
|
|
mtstate->mt_merge_subcommands |= MERGE_UPDATE;
|
|
break;
|
|
case CMD_DELETE:
|
|
mtstate->mt_merge_subcommands |= MERGE_DELETE;
|
|
break;
|
|
case CMD_NOTHING:
|
|
break;
|
|
default:
|
|
elog(ERROR, "unknown operation");
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Initializes the tuple slots in a ResultRelInfo for any MERGE action.
|
|
*
|
|
* We mark 'projectNewInfoValid' even though the projections themselves
|
|
* are not initialized here.
|
|
*/
|
|
void
|
|
ExecInitMergeTupleSlots(ModifyTableState *mtstate,
|
|
ResultRelInfo *resultRelInfo)
|
|
{
|
|
EState *estate = mtstate->ps.state;
|
|
|
|
Assert(!resultRelInfo->ri_projectNewInfoValid);
|
|
|
|
resultRelInfo->ri_oldTupleSlot =
|
|
table_slot_create(resultRelInfo->ri_RelationDesc,
|
|
&estate->es_tupleTable);
|
|
resultRelInfo->ri_newTupleSlot =
|
|
table_slot_create(resultRelInfo->ri_RelationDesc,
|
|
&estate->es_tupleTable);
|
|
resultRelInfo->ri_projectNewInfoValid = true;
|
|
}
|
|
|
|
/*
|
|
* Process BEFORE EACH STATEMENT triggers
|
|
*/
|
|
static void
|
|
fireBSTriggers(ModifyTableState *node)
|
|
{
|
|
ModifyTable *plan = (ModifyTable *) node->ps.plan;
|
|
ResultRelInfo *resultRelInfo = node->rootResultRelInfo;
|
|
|
|
switch (node->operation)
|
|
{
|
|
case CMD_INSERT:
|
|
ExecBSInsertTriggers(node->ps.state, resultRelInfo);
|
|
if (plan->onConflictAction == ONCONFLICT_UPDATE)
|
|
ExecBSUpdateTriggers(node->ps.state,
|
|
resultRelInfo);
|
|
break;
|
|
case CMD_UPDATE:
|
|
ExecBSUpdateTriggers(node->ps.state, resultRelInfo);
|
|
break;
|
|
case CMD_DELETE:
|
|
ExecBSDeleteTriggers(node->ps.state, resultRelInfo);
|
|
break;
|
|
case CMD_MERGE:
|
|
if (node->mt_merge_subcommands & MERGE_INSERT)
|
|
ExecBSInsertTriggers(node->ps.state, resultRelInfo);
|
|
if (node->mt_merge_subcommands & MERGE_UPDATE)
|
|
ExecBSUpdateTriggers(node->ps.state, resultRelInfo);
|
|
if (node->mt_merge_subcommands & MERGE_DELETE)
|
|
ExecBSDeleteTriggers(node->ps.state, resultRelInfo);
|
|
break;
|
|
default:
|
|
elog(ERROR, "unknown operation");
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Process AFTER EACH STATEMENT triggers
|
|
*/
|
|
static void
|
|
fireASTriggers(ModifyTableState *node)
|
|
{
|
|
ModifyTable *plan = (ModifyTable *) node->ps.plan;
|
|
ResultRelInfo *resultRelInfo = node->rootResultRelInfo;
|
|
|
|
switch (node->operation)
|
|
{
|
|
case CMD_INSERT:
|
|
if (plan->onConflictAction == ONCONFLICT_UPDATE)
|
|
ExecASUpdateTriggers(node->ps.state,
|
|
resultRelInfo,
|
|
node->mt_oc_transition_capture);
|
|
ExecASInsertTriggers(node->ps.state, resultRelInfo,
|
|
node->mt_transition_capture);
|
|
break;
|
|
case CMD_UPDATE:
|
|
ExecASUpdateTriggers(node->ps.state, resultRelInfo,
|
|
node->mt_transition_capture);
|
|
break;
|
|
case CMD_DELETE:
|
|
ExecASDeleteTriggers(node->ps.state, resultRelInfo,
|
|
node->mt_transition_capture);
|
|
break;
|
|
case CMD_MERGE:
|
|
if (node->mt_merge_subcommands & MERGE_DELETE)
|
|
ExecASDeleteTriggers(node->ps.state, resultRelInfo,
|
|
node->mt_transition_capture);
|
|
if (node->mt_merge_subcommands & MERGE_UPDATE)
|
|
ExecASUpdateTriggers(node->ps.state, resultRelInfo,
|
|
node->mt_transition_capture);
|
|
if (node->mt_merge_subcommands & MERGE_INSERT)
|
|
ExecASInsertTriggers(node->ps.state, resultRelInfo,
|
|
node->mt_transition_capture);
|
|
break;
|
|
default:
|
|
elog(ERROR, "unknown operation");
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Set up the state needed for collecting transition tuples for AFTER
|
|
* triggers.
|
|
*/
|
|
static void
|
|
ExecSetupTransitionCaptureState(ModifyTableState *mtstate, EState *estate)
|
|
{
|
|
ModifyTable *plan = (ModifyTable *) mtstate->ps.plan;
|
|
ResultRelInfo *targetRelInfo = mtstate->rootResultRelInfo;
|
|
|
|
/* Check for transition tables on the directly targeted relation. */
|
|
mtstate->mt_transition_capture =
|
|
MakeTransitionCaptureState(targetRelInfo->ri_TrigDesc,
|
|
RelationGetRelid(targetRelInfo->ri_RelationDesc),
|
|
mtstate->operation);
|
|
if (plan->operation == CMD_INSERT &&
|
|
plan->onConflictAction == ONCONFLICT_UPDATE)
|
|
mtstate->mt_oc_transition_capture =
|
|
MakeTransitionCaptureState(targetRelInfo->ri_TrigDesc,
|
|
RelationGetRelid(targetRelInfo->ri_RelationDesc),
|
|
CMD_UPDATE);
|
|
}
|
|
|
|
/*
|
|
* ExecPrepareTupleRouting --- prepare for routing one tuple
|
|
*
|
|
* Determine the partition in which the tuple in slot is to be inserted,
|
|
* and return its ResultRelInfo in *partRelInfo. The return value is
|
|
* a slot holding the tuple of the partition rowtype.
|
|
*
|
|
* This also sets the transition table information in mtstate based on the
|
|
* selected partition.
|
|
*/
|
|
static TupleTableSlot *
|
|
ExecPrepareTupleRouting(ModifyTableState *mtstate,
|
|
EState *estate,
|
|
PartitionTupleRouting *proute,
|
|
ResultRelInfo *targetRelInfo,
|
|
TupleTableSlot *slot,
|
|
ResultRelInfo **partRelInfo)
|
|
{
|
|
ResultRelInfo *partrel;
|
|
TupleConversionMap *map;
|
|
|
|
/*
|
|
* Lookup the target partition's ResultRelInfo. If ExecFindPartition does
|
|
* not find a valid partition for the tuple in 'slot' then an error is
|
|
* raised. An error may also be raised if the found partition is not a
|
|
* valid target for INSERTs. This is required since a partitioned table
|
|
* UPDATE to another partition becomes a DELETE+INSERT.
|
|
*/
|
|
partrel = ExecFindPartition(mtstate, targetRelInfo, proute, slot, estate);
|
|
|
|
/*
|
|
* If we're capturing transition tuples, we might need to convert from the
|
|
* partition rowtype to root partitioned table's rowtype. But if there
|
|
* are no BEFORE triggers on the partition that could change the tuple, we
|
|
* can just remember the original unconverted tuple to avoid a needless
|
|
* round trip conversion.
|
|
*/
|
|
if (mtstate->mt_transition_capture != NULL)
|
|
{
|
|
bool has_before_insert_row_trig;
|
|
|
|
has_before_insert_row_trig = (partrel->ri_TrigDesc &&
|
|
partrel->ri_TrigDesc->trig_insert_before_row);
|
|
|
|
mtstate->mt_transition_capture->tcs_original_insert_tuple =
|
|
!has_before_insert_row_trig ? slot : NULL;
|
|
}
|
|
|
|
/*
|
|
* Convert the tuple, if necessary.
|
|
*/
|
|
map = ExecGetRootToChildMap(partrel, estate);
|
|
if (map != NULL)
|
|
{
|
|
TupleTableSlot *new_slot = partrel->ri_PartitionTupleSlot;
|
|
|
|
slot = execute_attr_map_slot(map->attrMap, slot, new_slot);
|
|
}
|
|
|
|
*partRelInfo = partrel;
|
|
return slot;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecModifyTable
|
|
*
|
|
* Perform table modifications as required, and return RETURNING results
|
|
* if needed.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
static TupleTableSlot *
|
|
ExecModifyTable(PlanState *pstate)
|
|
{
|
|
ModifyTableState *node = castNode(ModifyTableState, pstate);
|
|
ModifyTableContext context;
|
|
EState *estate = node->ps.state;
|
|
CmdType operation = node->operation;
|
|
ResultRelInfo *resultRelInfo;
|
|
PlanState *subplanstate;
|
|
TupleTableSlot *slot;
|
|
TupleTableSlot *oldSlot;
|
|
ItemPointerData tuple_ctid;
|
|
HeapTupleData oldtupdata;
|
|
HeapTuple oldtuple;
|
|
ItemPointer tupleid;
|
|
|
|
CHECK_FOR_INTERRUPTS();
|
|
|
|
/*
|
|
* This should NOT get called during EvalPlanQual; we should have passed a
|
|
* subplan tree to EvalPlanQual, instead. Use a runtime test not just
|
|
* Assert because this condition is easy to miss in testing. (Note:
|
|
* although ModifyTable should not get executed within an EvalPlanQual
|
|
* operation, we do have to allow it to be initialized and shut down in
|
|
* case it is within a CTE subplan. Hence this test must be here, not in
|
|
* ExecInitModifyTable.)
|
|
*/
|
|
if (estate->es_epq_active != NULL)
|
|
elog(ERROR, "ModifyTable should not be called during EvalPlanQual");
|
|
|
|
/*
|
|
* If we've already completed processing, don't try to do more. We need
|
|
* this test because ExecPostprocessPlan might call us an extra time, and
|
|
* our subplan's nodes aren't necessarily robust against being called
|
|
* extra times.
|
|
*/
|
|
if (node->mt_done)
|
|
return NULL;
|
|
|
|
/*
|
|
* On first call, fire BEFORE STATEMENT triggers before proceeding.
|
|
*/
|
|
if (node->fireBSTriggers)
|
|
{
|
|
fireBSTriggers(node);
|
|
node->fireBSTriggers = false;
|
|
}
|
|
|
|
/* Preload local variables */
|
|
resultRelInfo = node->resultRelInfo + node->mt_lastResultIndex;
|
|
subplanstate = outerPlanState(node);
|
|
|
|
/* Set global context */
|
|
context.mtstate = node;
|
|
context.epqstate = &node->mt_epqstate;
|
|
context.estate = estate;
|
|
|
|
/*
|
|
* Fetch rows from subplan, and execute the required table modification
|
|
* for each row.
|
|
*/
|
|
for (;;)
|
|
{
|
|
/*
|
|
* Reset the per-output-tuple exprcontext. This is needed because
|
|
* triggers expect to use that context as workspace. It's a bit ugly
|
|
* to do this below the top level of the plan, however. We might need
|
|
* to rethink this later.
|
|
*/
|
|
ResetPerTupleExprContext(estate);
|
|
|
|
/*
|
|
* Reset per-tuple memory context used for processing on conflict and
|
|
* returning clauses, to free any expression evaluation storage
|
|
* allocated in the previous cycle.
|
|
*/
|
|
if (pstate->ps_ExprContext)
|
|
ResetExprContext(pstate->ps_ExprContext);
|
|
|
|
context.planSlot = ExecProcNode(subplanstate);
|
|
|
|
/* No more tuples to process? */
|
|
if (TupIsNull(context.planSlot))
|
|
break;
|
|
|
|
/*
|
|
* When there are multiple result relations, each tuple contains a
|
|
* junk column that gives the OID of the rel from which it came.
|
|
* Extract it and select the correct result relation.
|
|
*/
|
|
if (AttributeNumberIsValid(node->mt_resultOidAttno))
|
|
{
|
|
Datum datum;
|
|
bool isNull;
|
|
Oid resultoid;
|
|
|
|
datum = ExecGetJunkAttribute(context.planSlot, node->mt_resultOidAttno,
|
|
&isNull);
|
|
if (isNull)
|
|
{
|
|
/*
|
|
* For commands other than MERGE, any tuples having InvalidOid
|
|
* for tableoid are errors. For MERGE, we may need to handle
|
|
* them as WHEN NOT MATCHED clauses if any, so do that.
|
|
*
|
|
* Note that we use the node's toplevel resultRelInfo, not any
|
|
* specific partition's.
|
|
*/
|
|
if (operation == CMD_MERGE)
|
|
{
|
|
EvalPlanQualSetSlot(&node->mt_epqstate, context.planSlot);
|
|
|
|
ExecMerge(&context, node->resultRelInfo, NULL, node->canSetTag);
|
|
continue; /* no RETURNING support yet */
|
|
}
|
|
|
|
elog(ERROR, "tableoid is NULL");
|
|
}
|
|
resultoid = DatumGetObjectId(datum);
|
|
|
|
/* If it's not the same as last time, we need to locate the rel */
|
|
if (resultoid != node->mt_lastResultOid)
|
|
resultRelInfo = ExecLookupResultRelByOid(node, resultoid,
|
|
false, true);
|
|
}
|
|
|
|
/*
|
|
* If resultRelInfo->ri_usesFdwDirectModify is true, all we need to do
|
|
* here is compute the RETURNING expressions.
|
|
*/
|
|
if (resultRelInfo->ri_usesFdwDirectModify)
|
|
{
|
|
Assert(resultRelInfo->ri_projectReturning);
|
|
|
|
/*
|
|
* A scan slot containing the data that was actually inserted,
|
|
* updated or deleted has already been made available to
|
|
* ExecProcessReturning by IterateDirectModify, so no need to
|
|
* provide it here.
|
|
*/
|
|
slot = ExecProcessReturning(resultRelInfo, NULL, context.planSlot);
|
|
|
|
return slot;
|
|
}
|
|
|
|
EvalPlanQualSetSlot(&node->mt_epqstate, context.planSlot);
|
|
slot = context.planSlot;
|
|
|
|
tupleid = NULL;
|
|
oldtuple = NULL;
|
|
|
|
/*
|
|
* For UPDATE/DELETE/MERGE, fetch the row identity info for the tuple
|
|
* to be updated/deleted/merged. For a heap relation, that's a TID;
|
|
* otherwise we may have a wholerow junk attr that carries the old
|
|
* tuple in toto. Keep this in step with the part of
|
|
* ExecInitModifyTable that sets up ri_RowIdAttNo.
|
|
*/
|
|
if (operation == CMD_UPDATE || operation == CMD_DELETE ||
|
|
operation == CMD_MERGE)
|
|
{
|
|
char relkind;
|
|
Datum datum;
|
|
bool isNull;
|
|
|
|
relkind = resultRelInfo->ri_RelationDesc->rd_rel->relkind;
|
|
if (relkind == RELKIND_RELATION ||
|
|
relkind == RELKIND_MATVIEW ||
|
|
relkind == RELKIND_PARTITIONED_TABLE)
|
|
{
|
|
/* ri_RowIdAttNo refers to a ctid attribute */
|
|
Assert(AttributeNumberIsValid(resultRelInfo->ri_RowIdAttNo));
|
|
datum = ExecGetJunkAttribute(slot,
|
|
resultRelInfo->ri_RowIdAttNo,
|
|
&isNull);
|
|
|
|
/*
|
|
* For commands other than MERGE, any tuples having a null row
|
|
* identifier are errors. For MERGE, we may need to handle
|
|
* them as WHEN NOT MATCHED clauses if any, so do that.
|
|
*
|
|
* Note that we use the node's toplevel resultRelInfo, not any
|
|
* specific partition's.
|
|
*/
|
|
if (isNull)
|
|
{
|
|
if (operation == CMD_MERGE)
|
|
{
|
|
EvalPlanQualSetSlot(&node->mt_epqstate, context.planSlot);
|
|
|
|
ExecMerge(&context, node->resultRelInfo, NULL, node->canSetTag);
|
|
continue; /* no RETURNING support yet */
|
|
}
|
|
|
|
elog(ERROR, "ctid is NULL");
|
|
}
|
|
|
|
tupleid = (ItemPointer) DatumGetPointer(datum);
|
|
tuple_ctid = *tupleid; /* be sure we don't free ctid!! */
|
|
tupleid = &tuple_ctid;
|
|
}
|
|
|
|
/*
|
|
* Use the wholerow attribute, when available, to reconstruct the
|
|
* old relation tuple. The old tuple serves one or both of two
|
|
* purposes: 1) it serves as the OLD tuple for row triggers, 2) it
|
|
* provides values for any unchanged columns for the NEW tuple of
|
|
* an UPDATE, because the subplan does not produce all the columns
|
|
* of the target table.
|
|
*
|
|
* Note that the wholerow attribute does not carry system columns,
|
|
* so foreign table triggers miss seeing those, except that we
|
|
* know enough here to set t_tableOid. Quite separately from
|
|
* this, the FDW may fetch its own junk attrs to identify the row.
|
|
*
|
|
* Other relevant relkinds, currently limited to views, always
|
|
* have a wholerow attribute.
|
|
*/
|
|
else if (AttributeNumberIsValid(resultRelInfo->ri_RowIdAttNo))
|
|
{
|
|
datum = ExecGetJunkAttribute(slot,
|
|
resultRelInfo->ri_RowIdAttNo,
|
|
&isNull);
|
|
/* shouldn't ever get a null result... */
|
|
if (isNull)
|
|
elog(ERROR, "wholerow is NULL");
|
|
|
|
oldtupdata.t_data = DatumGetHeapTupleHeader(datum);
|
|
oldtupdata.t_len =
|
|
HeapTupleHeaderGetDatumLength(oldtupdata.t_data);
|
|
ItemPointerSetInvalid(&(oldtupdata.t_self));
|
|
/* Historically, view triggers see invalid t_tableOid. */
|
|
oldtupdata.t_tableOid =
|
|
(relkind == RELKIND_VIEW) ? InvalidOid :
|
|
RelationGetRelid(resultRelInfo->ri_RelationDesc);
|
|
|
|
oldtuple = &oldtupdata;
|
|
}
|
|
else
|
|
{
|
|
/* Only foreign tables are allowed to omit a row-ID attr */
|
|
Assert(relkind == RELKIND_FOREIGN_TABLE);
|
|
}
|
|
}
|
|
|
|
switch (operation)
|
|
{
|
|
case CMD_INSERT:
|
|
/* Initialize projection info if first time for this table */
|
|
if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
|
|
ExecInitInsertProjection(node, resultRelInfo);
|
|
slot = ExecGetInsertNewTuple(resultRelInfo, context.planSlot);
|
|
slot = ExecInsert(&context, resultRelInfo, slot,
|
|
node->canSetTag, NULL, NULL);
|
|
break;
|
|
|
|
case CMD_UPDATE:
|
|
/* Initialize projection info if first time for this table */
|
|
if (unlikely(!resultRelInfo->ri_projectNewInfoValid))
|
|
ExecInitUpdateProjection(node, resultRelInfo);
|
|
|
|
/*
|
|
* Make the new tuple by combining plan's output tuple with
|
|
* the old tuple being updated.
|
|
*/
|
|
oldSlot = resultRelInfo->ri_oldTupleSlot;
|
|
if (oldtuple != NULL)
|
|
{
|
|
/* Use the wholerow junk attr as the old tuple. */
|
|
ExecForceStoreHeapTuple(oldtuple, oldSlot, false);
|
|
}
|
|
else
|
|
{
|
|
/* Fetch the most recent version of old tuple. */
|
|
Relation relation = resultRelInfo->ri_RelationDesc;
|
|
|
|
if (!table_tuple_fetch_row_version(relation, tupleid,
|
|
SnapshotAny,
|
|
oldSlot))
|
|
elog(ERROR, "failed to fetch tuple being updated");
|
|
}
|
|
slot = ExecGetUpdateNewTuple(resultRelInfo, context.planSlot,
|
|
oldSlot);
|
|
context.relaction = NULL;
|
|
|
|
/* Now apply the update. */
|
|
slot = ExecUpdate(&context, resultRelInfo, tupleid, oldtuple,
|
|
slot, node->canSetTag);
|
|
break;
|
|
|
|
case CMD_DELETE:
|
|
slot = ExecDelete(&context, resultRelInfo, tupleid, oldtuple,
|
|
true, false, node->canSetTag, NULL, NULL, NULL);
|
|
break;
|
|
|
|
case CMD_MERGE:
|
|
slot = ExecMerge(&context, resultRelInfo, tupleid, node->canSetTag);
|
|
break;
|
|
|
|
default:
|
|
elog(ERROR, "unknown operation");
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* If we got a RETURNING result, return it to caller. We'll continue
|
|
* the work on next call.
|
|
*/
|
|
if (slot)
|
|
return slot;
|
|
}
|
|
|
|
/*
|
|
* Insert remaining tuples for batch insert.
|
|
*/
|
|
if (estate->es_insert_pending_result_relations != NIL)
|
|
ExecPendingInserts(estate);
|
|
|
|
/*
|
|
* We're done, but fire AFTER STATEMENT triggers before exiting.
|
|
*/
|
|
fireASTriggers(node);
|
|
|
|
node->mt_done = true;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* ExecLookupResultRelByOid
|
|
* If the table with given OID is among the result relations to be
|
|
* updated by the given ModifyTable node, return its ResultRelInfo.
|
|
*
|
|
* If not found, return NULL if missing_ok, else raise error.
|
|
*
|
|
* If update_cache is true, then upon successful lookup, update the node's
|
|
* one-element cache. ONLY ExecModifyTable may pass true for this.
|
|
*/
|
|
ResultRelInfo *
|
|
ExecLookupResultRelByOid(ModifyTableState *node, Oid resultoid,
|
|
bool missing_ok, bool update_cache)
|
|
{
|
|
if (node->mt_resultOidHash)
|
|
{
|
|
/* Use the pre-built hash table to locate the rel */
|
|
MTTargetRelLookup *mtlookup;
|
|
|
|
mtlookup = (MTTargetRelLookup *)
|
|
hash_search(node->mt_resultOidHash, &resultoid, HASH_FIND, NULL);
|
|
if (mtlookup)
|
|
{
|
|
if (update_cache)
|
|
{
|
|
node->mt_lastResultOid = resultoid;
|
|
node->mt_lastResultIndex = mtlookup->relationIndex;
|
|
}
|
|
return node->resultRelInfo + mtlookup->relationIndex;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* With few target rels, just search the ResultRelInfo array */
|
|
for (int ndx = 0; ndx < node->mt_nrels; ndx++)
|
|
{
|
|
ResultRelInfo *rInfo = node->resultRelInfo + ndx;
|
|
|
|
if (RelationGetRelid(rInfo->ri_RelationDesc) == resultoid)
|
|
{
|
|
if (update_cache)
|
|
{
|
|
node->mt_lastResultOid = resultoid;
|
|
node->mt_lastResultIndex = ndx;
|
|
}
|
|
return rInfo;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!missing_ok)
|
|
elog(ERROR, "incorrect result relation OID %u", resultoid);
|
|
return NULL;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecInitModifyTable
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
ModifyTableState *
|
|
ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags)
|
|
{
|
|
ModifyTableState *mtstate;
|
|
Plan *subplan = outerPlan(node);
|
|
CmdType operation = node->operation;
|
|
int nrels = list_length(node->resultRelations);
|
|
ResultRelInfo *resultRelInfo;
|
|
List *arowmarks;
|
|
ListCell *l;
|
|
int i;
|
|
Relation rel;
|
|
|
|
/* check for unsupported flags */
|
|
Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)));
|
|
|
|
/*
|
|
* create state structure
|
|
*/
|
|
mtstate = makeNode(ModifyTableState);
|
|
mtstate->ps.plan = (Plan *) node;
|
|
mtstate->ps.state = estate;
|
|
mtstate->ps.ExecProcNode = ExecModifyTable;
|
|
|
|
mtstate->operation = operation;
|
|
mtstate->canSetTag = node->canSetTag;
|
|
mtstate->mt_done = false;
|
|
|
|
mtstate->mt_nrels = nrels;
|
|
mtstate->resultRelInfo = (ResultRelInfo *)
|
|
palloc(nrels * sizeof(ResultRelInfo));
|
|
|
|
mtstate->mt_merge_inserted = 0;
|
|
mtstate->mt_merge_updated = 0;
|
|
mtstate->mt_merge_deleted = 0;
|
|
|
|
/*----------
|
|
* Resolve the target relation. This is the same as:
|
|
*
|
|
* - the relation for which we will fire FOR STATEMENT triggers,
|
|
* - the relation into whose tuple format all captured transition tuples
|
|
* must be converted, and
|
|
* - the root partitioned table used for tuple routing.
|
|
*
|
|
* If it's a partitioned or inherited table, the root partition or
|
|
* appendrel RTE doesn't appear elsewhere in the plan and its RT index is
|
|
* given explicitly in node->rootRelation. Otherwise, the target relation
|
|
* is the sole relation in the node->resultRelations list.
|
|
*----------
|
|
*/
|
|
if (node->rootRelation > 0)
|
|
{
|
|
mtstate->rootResultRelInfo = makeNode(ResultRelInfo);
|
|
ExecInitResultRelation(estate, mtstate->rootResultRelInfo,
|
|
node->rootRelation);
|
|
}
|
|
else
|
|
{
|
|
Assert(list_length(node->resultRelations) == 1);
|
|
mtstate->rootResultRelInfo = mtstate->resultRelInfo;
|
|
ExecInitResultRelation(estate, mtstate->resultRelInfo,
|
|
linitial_int(node->resultRelations));
|
|
}
|
|
|
|
/* set up epqstate with dummy subplan data for the moment */
|
|
EvalPlanQualInit(&mtstate->mt_epqstate, estate, NULL, NIL,
|
|
node->epqParam, node->resultRelations);
|
|
mtstate->fireBSTriggers = true;
|
|
|
|
/*
|
|
* Build state for collecting transition tuples. This requires having a
|
|
* valid trigger query context, so skip it in explain-only mode.
|
|
*/
|
|
if (!(eflags & EXEC_FLAG_EXPLAIN_ONLY))
|
|
ExecSetupTransitionCaptureState(mtstate, estate);
|
|
|
|
/*
|
|
* Open all the result relations and initialize the ResultRelInfo structs.
|
|
* (But root relation was initialized above, if it's part of the array.)
|
|
* We must do this before initializing the subplan, because direct-modify
|
|
* FDWs expect their ResultRelInfos to be available.
|
|
*/
|
|
resultRelInfo = mtstate->resultRelInfo;
|
|
i = 0;
|
|
foreach(l, node->resultRelations)
|
|
{
|
|
Index resultRelation = lfirst_int(l);
|
|
|
|
if (resultRelInfo != mtstate->rootResultRelInfo)
|
|
{
|
|
ExecInitResultRelation(estate, resultRelInfo, resultRelation);
|
|
|
|
/*
|
|
* For child result relations, store the root result relation
|
|
* pointer. We do so for the convenience of places that want to
|
|
* look at the query's original target relation but don't have the
|
|
* mtstate handy.
|
|
*/
|
|
resultRelInfo->ri_RootResultRelInfo = mtstate->rootResultRelInfo;
|
|
}
|
|
|
|
/* Initialize the usesFdwDirectModify flag */
|
|
resultRelInfo->ri_usesFdwDirectModify =
|
|
bms_is_member(i, node->fdwDirectModifyPlans);
|
|
|
|
/*
|
|
* Verify result relation is a valid target for the current operation
|
|
*/
|
|
CheckValidResultRel(resultRelInfo, operation);
|
|
|
|
resultRelInfo++;
|
|
i++;
|
|
}
|
|
|
|
/*
|
|
* Now we may initialize the subplan.
|
|
*/
|
|
outerPlanState(mtstate) = ExecInitNode(subplan, estate, eflags);
|
|
|
|
/*
|
|
* Do additional per-result-relation initialization.
|
|
*/
|
|
for (i = 0; i < nrels; i++)
|
|
{
|
|
resultRelInfo = &mtstate->resultRelInfo[i];
|
|
|
|
/* Let FDWs init themselves for foreign-table result rels */
|
|
if (!resultRelInfo->ri_usesFdwDirectModify &&
|
|
resultRelInfo->ri_FdwRoutine != NULL &&
|
|
resultRelInfo->ri_FdwRoutine->BeginForeignModify != NULL)
|
|
{
|
|
List *fdw_private = (List *) list_nth(node->fdwPrivLists, i);
|
|
|
|
resultRelInfo->ri_FdwRoutine->BeginForeignModify(mtstate,
|
|
resultRelInfo,
|
|
fdw_private,
|
|
i,
|
|
eflags);
|
|
}
|
|
|
|
/*
|
|
* For UPDATE/DELETE/MERGE, find the appropriate junk attr now, either
|
|
* a 'ctid' or 'wholerow' attribute depending on relkind. For foreign
|
|
* tables, the FDW might have created additional junk attr(s), but
|
|
* those are no concern of ours.
|
|
*/
|
|
if (operation == CMD_UPDATE || operation == CMD_DELETE ||
|
|
operation == CMD_MERGE)
|
|
{
|
|
char relkind;
|
|
|
|
relkind = resultRelInfo->ri_RelationDesc->rd_rel->relkind;
|
|
if (relkind == RELKIND_RELATION ||
|
|
relkind == RELKIND_MATVIEW ||
|
|
relkind == RELKIND_PARTITIONED_TABLE)
|
|
{
|
|
resultRelInfo->ri_RowIdAttNo =
|
|
ExecFindJunkAttributeInTlist(subplan->targetlist, "ctid");
|
|
if (!AttributeNumberIsValid(resultRelInfo->ri_RowIdAttNo))
|
|
elog(ERROR, "could not find junk ctid column");
|
|
}
|
|
else if (relkind == RELKIND_FOREIGN_TABLE)
|
|
{
|
|
/*
|
|
* We don't support MERGE with foreign tables for now. (It's
|
|
* problematic because the implementation uses CTID.)
|
|
*/
|
|
Assert(operation != CMD_MERGE);
|
|
|
|
/*
|
|
* When there is a row-level trigger, there should be a
|
|
* wholerow attribute. We also require it to be present in
|
|
* UPDATE and MERGE, so we can get the values of unchanged
|
|
* columns.
|
|
*/
|
|
resultRelInfo->ri_RowIdAttNo =
|
|
ExecFindJunkAttributeInTlist(subplan->targetlist,
|
|
"wholerow");
|
|
if ((mtstate->operation == CMD_UPDATE || mtstate->operation == CMD_MERGE) &&
|
|
!AttributeNumberIsValid(resultRelInfo->ri_RowIdAttNo))
|
|
elog(ERROR, "could not find junk wholerow column");
|
|
}
|
|
else
|
|
{
|
|
/* No support for MERGE */
|
|
Assert(operation != CMD_MERGE);
|
|
/* Other valid target relkinds must provide wholerow */
|
|
resultRelInfo->ri_RowIdAttNo =
|
|
ExecFindJunkAttributeInTlist(subplan->targetlist,
|
|
"wholerow");
|
|
if (!AttributeNumberIsValid(resultRelInfo->ri_RowIdAttNo))
|
|
elog(ERROR, "could not find junk wholerow column");
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If this is an inherited update/delete/merge, there will be a junk
|
|
* attribute named "tableoid" present in the subplan's targetlist. It
|
|
* will be used to identify the result relation for a given tuple to be
|
|
* updated/deleted/merged.
|
|
*/
|
|
mtstate->mt_resultOidAttno =
|
|
ExecFindJunkAttributeInTlist(subplan->targetlist, "tableoid");
|
|
Assert(AttributeNumberIsValid(mtstate->mt_resultOidAttno) || nrels == 1);
|
|
mtstate->mt_lastResultOid = InvalidOid; /* force lookup at first tuple */
|
|
mtstate->mt_lastResultIndex = 0; /* must be zero if no such attr */
|
|
|
|
/* Get the root target relation */
|
|
rel = mtstate->rootResultRelInfo->ri_RelationDesc;
|
|
|
|
/*
|
|
* Build state for tuple routing if it's a partitioned INSERT. An UPDATE
|
|
* or MERGE might need this too, but only if it actually moves tuples
|
|
* between partitions; in that case setup is done by
|
|
* ExecCrossPartitionUpdate.
|
|
*/
|
|
if (rel->rd_rel->relkind == RELKIND_PARTITIONED_TABLE &&
|
|
operation == CMD_INSERT)
|
|
mtstate->mt_partition_tuple_routing =
|
|
ExecSetupPartitionTupleRouting(estate, rel);
|
|
|
|
/*
|
|
* Initialize any WITH CHECK OPTION constraints if needed.
|
|
*/
|
|
resultRelInfo = mtstate->resultRelInfo;
|
|
foreach(l, node->withCheckOptionLists)
|
|
{
|
|
List *wcoList = (List *) lfirst(l);
|
|
List *wcoExprs = NIL;
|
|
ListCell *ll;
|
|
|
|
foreach(ll, wcoList)
|
|
{
|
|
WithCheckOption *wco = (WithCheckOption *) lfirst(ll);
|
|
ExprState *wcoExpr = ExecInitQual((List *) wco->qual,
|
|
&mtstate->ps);
|
|
|
|
wcoExprs = lappend(wcoExprs, wcoExpr);
|
|
}
|
|
|
|
resultRelInfo->ri_WithCheckOptions = wcoList;
|
|
resultRelInfo->ri_WithCheckOptionExprs = wcoExprs;
|
|
resultRelInfo++;
|
|
}
|
|
|
|
/*
|
|
* Initialize RETURNING projections if needed.
|
|
*/
|
|
if (node->returningLists)
|
|
{
|
|
TupleTableSlot *slot;
|
|
ExprContext *econtext;
|
|
|
|
/*
|
|
* Initialize result tuple slot and assign its rowtype using the first
|
|
* RETURNING list. We assume the rest will look the same.
|
|
*/
|
|
mtstate->ps.plan->targetlist = (List *) linitial(node->returningLists);
|
|
|
|
/* Set up a slot for the output of the RETURNING projection(s) */
|
|
ExecInitResultTupleSlotTL(&mtstate->ps, &TTSOpsVirtual);
|
|
slot = mtstate->ps.ps_ResultTupleSlot;
|
|
|
|
/* Need an econtext too */
|
|
if (mtstate->ps.ps_ExprContext == NULL)
|
|
ExecAssignExprContext(estate, &mtstate->ps);
|
|
econtext = mtstate->ps.ps_ExprContext;
|
|
|
|
/*
|
|
* Build a projection for each result rel.
|
|
*/
|
|
resultRelInfo = mtstate->resultRelInfo;
|
|
foreach(l, node->returningLists)
|
|
{
|
|
List *rlist = (List *) lfirst(l);
|
|
|
|
resultRelInfo->ri_returningList = rlist;
|
|
resultRelInfo->ri_projectReturning =
|
|
ExecBuildProjectionInfo(rlist, econtext, slot, &mtstate->ps,
|
|
resultRelInfo->ri_RelationDesc->rd_att);
|
|
resultRelInfo++;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/*
|
|
* We still must construct a dummy result tuple type, because InitPlan
|
|
* expects one (maybe should change that?).
|
|
*/
|
|
mtstate->ps.plan->targetlist = NIL;
|
|
ExecInitResultTypeTL(&mtstate->ps);
|
|
|
|
mtstate->ps.ps_ExprContext = NULL;
|
|
}
|
|
|
|
/* Set the list of arbiter indexes if needed for ON CONFLICT */
|
|
resultRelInfo = mtstate->resultRelInfo;
|
|
if (node->onConflictAction != ONCONFLICT_NONE)
|
|
{
|
|
/* insert may only have one relation, inheritance is not expanded */
|
|
Assert(nrels == 1);
|
|
resultRelInfo->ri_onConflictArbiterIndexes = node->arbiterIndexes;
|
|
}
|
|
|
|
/*
|
|
* If needed, Initialize target list, projection and qual for ON CONFLICT
|
|
* DO UPDATE.
|
|
*/
|
|
if (node->onConflictAction == ONCONFLICT_UPDATE)
|
|
{
|
|
OnConflictSetState *onconfl = makeNode(OnConflictSetState);
|
|
ExprContext *econtext;
|
|
TupleDesc relationDesc;
|
|
|
|
/* already exists if created by RETURNING processing above */
|
|
if (mtstate->ps.ps_ExprContext == NULL)
|
|
ExecAssignExprContext(estate, &mtstate->ps);
|
|
|
|
econtext = mtstate->ps.ps_ExprContext;
|
|
relationDesc = resultRelInfo->ri_RelationDesc->rd_att;
|
|
|
|
/* create state for DO UPDATE SET operation */
|
|
resultRelInfo->ri_onConflict = onconfl;
|
|
|
|
/* initialize slot for the existing tuple */
|
|
onconfl->oc_Existing =
|
|
table_slot_create(resultRelInfo->ri_RelationDesc,
|
|
&mtstate->ps.state->es_tupleTable);
|
|
|
|
/*
|
|
* Create the tuple slot for the UPDATE SET projection. We want a slot
|
|
* of the table's type here, because the slot will be used to insert
|
|
* into the table, and for RETURNING processing - which may access
|
|
* system attributes.
|
|
*/
|
|
onconfl->oc_ProjSlot =
|
|
table_slot_create(resultRelInfo->ri_RelationDesc,
|
|
&mtstate->ps.state->es_tupleTable);
|
|
|
|
/* build UPDATE SET projection state */
|
|
onconfl->oc_ProjInfo =
|
|
ExecBuildUpdateProjection(node->onConflictSet,
|
|
true,
|
|
node->onConflictCols,
|
|
relationDesc,
|
|
econtext,
|
|
onconfl->oc_ProjSlot,
|
|
&mtstate->ps);
|
|
|
|
/* initialize state to evaluate the WHERE clause, if any */
|
|
if (node->onConflictWhere)
|
|
{
|
|
ExprState *qualexpr;
|
|
|
|
qualexpr = ExecInitQual((List *) node->onConflictWhere,
|
|
&mtstate->ps);
|
|
onconfl->oc_WhereClause = qualexpr;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If we have any secondary relations in an UPDATE or DELETE, they need to
|
|
* be treated like non-locked relations in SELECT FOR UPDATE, i.e., the
|
|
* EvalPlanQual mechanism needs to be told about them. This also goes for
|
|
* the source relations in a MERGE. Locate the relevant ExecRowMarks.
|
|
*/
|
|
arowmarks = NIL;
|
|
foreach(l, node->rowMarks)
|
|
{
|
|
PlanRowMark *rc = lfirst_node(PlanRowMark, l);
|
|
ExecRowMark *erm;
|
|
ExecAuxRowMark *aerm;
|
|
|
|
/* ignore "parent" rowmarks; they are irrelevant at runtime */
|
|
if (rc->isParent)
|
|
continue;
|
|
|
|
/* Find ExecRowMark and build ExecAuxRowMark */
|
|
erm = ExecFindRowMark(estate, rc->rti, false);
|
|
aerm = ExecBuildAuxRowMark(erm, subplan->targetlist);
|
|
arowmarks = lappend(arowmarks, aerm);
|
|
}
|
|
|
|
/* For a MERGE command, initialize its state */
|
|
if (mtstate->operation == CMD_MERGE)
|
|
ExecInitMerge(mtstate, estate);
|
|
|
|
EvalPlanQualSetPlan(&mtstate->mt_epqstate, subplan, arowmarks);
|
|
|
|
/*
|
|
* If there are a lot of result relations, use a hash table to speed the
|
|
* lookups. If there are not a lot, a simple linear search is faster.
|
|
*
|
|
* It's not clear where the threshold is, but try 64 for starters. In a
|
|
* debugging build, use a small threshold so that we get some test
|
|
* coverage of both code paths.
|
|
*/
|
|
#ifdef USE_ASSERT_CHECKING
|
|
#define MT_NRELS_HASH 4
|
|
#else
|
|
#define MT_NRELS_HASH 64
|
|
#endif
|
|
if (nrels >= MT_NRELS_HASH)
|
|
{
|
|
HASHCTL hash_ctl;
|
|
|
|
hash_ctl.keysize = sizeof(Oid);
|
|
hash_ctl.entrysize = sizeof(MTTargetRelLookup);
|
|
hash_ctl.hcxt = CurrentMemoryContext;
|
|
mtstate->mt_resultOidHash =
|
|
hash_create("ModifyTable target hash",
|
|
nrels, &hash_ctl,
|
|
HASH_ELEM | HASH_BLOBS | HASH_CONTEXT);
|
|
for (i = 0; i < nrels; i++)
|
|
{
|
|
Oid hashkey;
|
|
MTTargetRelLookup *mtlookup;
|
|
bool found;
|
|
|
|
resultRelInfo = &mtstate->resultRelInfo[i];
|
|
hashkey = RelationGetRelid(resultRelInfo->ri_RelationDesc);
|
|
mtlookup = (MTTargetRelLookup *)
|
|
hash_search(mtstate->mt_resultOidHash, &hashkey,
|
|
HASH_ENTER, &found);
|
|
Assert(!found);
|
|
mtlookup->relationIndex = i;
|
|
}
|
|
}
|
|
else
|
|
mtstate->mt_resultOidHash = NULL;
|
|
|
|
/*
|
|
* Determine if the FDW supports batch insert and determine the batch size
|
|
* (a FDW may support batching, but it may be disabled for the
|
|
* server/table).
|
|
*
|
|
* We only do this for INSERT, so that for UPDATE/DELETE the batch size
|
|
* remains set to 0.
|
|
*/
|
|
if (operation == CMD_INSERT)
|
|
{
|
|
/* insert may only have one relation, inheritance is not expanded */
|
|
Assert(nrels == 1);
|
|
resultRelInfo = mtstate->resultRelInfo;
|
|
if (!resultRelInfo->ri_usesFdwDirectModify &&
|
|
resultRelInfo->ri_FdwRoutine != NULL &&
|
|
resultRelInfo->ri_FdwRoutine->GetForeignModifyBatchSize &&
|
|
resultRelInfo->ri_FdwRoutine->ExecForeignBatchInsert)
|
|
{
|
|
resultRelInfo->ri_BatchSize =
|
|
resultRelInfo->ri_FdwRoutine->GetForeignModifyBatchSize(resultRelInfo);
|
|
Assert(resultRelInfo->ri_BatchSize >= 1);
|
|
}
|
|
else
|
|
resultRelInfo->ri_BatchSize = 1;
|
|
}
|
|
|
|
/*
|
|
* Lastly, if this is not the primary (canSetTag) ModifyTable node, add it
|
|
* to estate->es_auxmodifytables so that it will be run to completion by
|
|
* ExecPostprocessPlan. (It'd actually work fine to add the primary
|
|
* ModifyTable node too, but there's no need.) Note the use of lcons not
|
|
* lappend: we need later-initialized ModifyTable nodes to be shut down
|
|
* before earlier ones. This ensures that we don't throw away RETURNING
|
|
* rows that need to be seen by a later CTE subplan.
|
|
*/
|
|
if (!mtstate->canSetTag)
|
|
estate->es_auxmodifytables = lcons(mtstate,
|
|
estate->es_auxmodifytables);
|
|
|
|
return mtstate;
|
|
}
|
|
|
|
/* ----------------------------------------------------------------
|
|
* ExecEndModifyTable
|
|
*
|
|
* Shuts down the plan.
|
|
*
|
|
* Returns nothing of interest.
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
void
|
|
ExecEndModifyTable(ModifyTableState *node)
|
|
{
|
|
int i;
|
|
|
|
/*
|
|
* Allow any FDWs to shut down
|
|
*/
|
|
for (i = 0; i < node->mt_nrels; i++)
|
|
{
|
|
int j;
|
|
ResultRelInfo *resultRelInfo = node->resultRelInfo + i;
|
|
|
|
if (!resultRelInfo->ri_usesFdwDirectModify &&
|
|
resultRelInfo->ri_FdwRoutine != NULL &&
|
|
resultRelInfo->ri_FdwRoutine->EndForeignModify != NULL)
|
|
resultRelInfo->ri_FdwRoutine->EndForeignModify(node->ps.state,
|
|
resultRelInfo);
|
|
|
|
/*
|
|
* Cleanup the initialized batch slots. This only matters for FDWs
|
|
* with batching, but the other cases will have ri_NumSlotsInitialized
|
|
* == 0.
|
|
*/
|
|
for (j = 0; j < resultRelInfo->ri_NumSlotsInitialized; j++)
|
|
{
|
|
ExecDropSingleTupleTableSlot(resultRelInfo->ri_Slots[j]);
|
|
ExecDropSingleTupleTableSlot(resultRelInfo->ri_PlanSlots[j]);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Close all the partitioned tables, leaf partitions, and their indices
|
|
* and release the slot used for tuple routing, if set.
|
|
*/
|
|
if (node->mt_partition_tuple_routing)
|
|
{
|
|
ExecCleanupTupleRouting(node, node->mt_partition_tuple_routing);
|
|
|
|
if (node->mt_root_tuple_slot)
|
|
ExecDropSingleTupleTableSlot(node->mt_root_tuple_slot);
|
|
}
|
|
|
|
/*
|
|
* Terminate EPQ execution if active
|
|
*/
|
|
EvalPlanQualEnd(&node->mt_epqstate);
|
|
|
|
/*
|
|
* shut down subplan
|
|
*/
|
|
ExecEndNode(outerPlanState(node));
|
|
}
|
|
|
|
void
|
|
ExecReScanModifyTable(ModifyTableState *node)
|
|
{
|
|
/*
|
|
* Currently, we don't need to support rescan on ModifyTable nodes. The
|
|
* semantics of that would be a bit debatable anyway.
|
|
*/
|
|
elog(ERROR, "ExecReScanModifyTable is not implemented");
|
|
}
|